问题
I am having some trouble using the android crossfading views. I'm trying to crossfade between 2 pictures back and forth. I can load the image, but once I hit the crossfade button, the app crashes. I tried following the code from the android site and modifying to fit my needs. I'm not quite sure if I have the XML file setup correctly to do the multiple views. I've tried the ImageViews inside of FrameLayout and without the FrameLayout also. Not sure how to set it up properly. Thanks for your time. I have included the java, xml, and logcat below:
MainActivty.java
public class MainActivity extends ActionBarActivity {
private View imageView1;
private View imageView2;
private int mShortAnimationDuration;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
if (savedInstanceState == null) {
getSupportFragmentManager().beginTransaction()
.add(R.id.container, new PlaceholderFragment()).commit();
}
imageView1 = findViewById(R.id.imageView1);
imageView2 = findViewById(R.id.imageView2);
// Initially hide the content view.
imageView2.setVisibility(View.GONE);
// Retrieve and cache the system's default "short" animation time.
mShortAnimationDuration = getResources().getInteger(android.R.integer.config_shortAnimTime);
}
private void crossfade() {
// Set the content view to 0% opacity but visible, so that it is visible
// (but fully transparent) during the animation.
imageView1.setAlpha(0f);
imageView1.setVisibility(View.VISIBLE);
// Animate the content view to 100% opacity, and clear any animation
// listener set on the view.
imageView1.animate()
.alpha(1f)
.setDuration(mShortAnimationDuration)
.setListener(null);
// Animate the loading view to 0% opacity. After the animation ends,
// set its visibility to GONE as an optimization step (it won't
// participate in layout passes, etc.)
imageView2.animate()
.alpha(0f)
.setDuration(mShortAnimationDuration)
.setListener(new AnimatorListenerAdapter() {
@Override
public void onAnimationEnd(Animator animation) {
imageView2.setVisibility(View.GONE);
}
});
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
/**
* A placeholder fragment containing a simple view.
*/
public static class PlaceholderFragment extends Fragment {
public PlaceholderFragment() {
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_main, container,
false);
return rootView;
}
}
}
XML
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/container"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="ca.mohawk.you.lab6a.MainActivity"
tools:ignore="MergeRootFrame">
<FrameLayout
android:layout_width="match_parent"
android:layout_height="match_parent">
<ImageView
android:id="@+id/imageView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true"
android:src="@drawable/desert" />
</FrameLayout>
<FrameLayout
android:layout_width="match_parent"
android:layout_height="match_parent">
<ImageView
android:id="@+id/imageView2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true"
android:src="@drawable/jellyfish" />
</FrameLayout>
<Button
android:id="@+id/button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerHorizontal="true"
android:layout_marginBottom="42dp"
android:text="@string/button_click"
android:onClick="crossfade" />
</RelativeLayout>
Logcat
04-07 23:25:25.770: D/dalvikvm(819): Not late-enabling CheckJNI (already on)
04-07 23:25:30.500: D/dalvikvm(819): GC_FOR_ALLOC freed 65K, 5% free 2900K/3048K, paused 47ms, total 49ms
04-07 23:25:30.500: I/dalvikvm-heap(819): Grow heap (frag case) to 9.659MB for 7077904-byte allocation
04-07 23:25:30.560: D/dalvikvm(819): GC_FOR_ALLOC freed 2K, 2% free 9810K/9964K, paused 53ms, total 53ms
04-07 23:25:31.860: D/dalvikvm(819): GC_FOR_ALLOC freed <1K, 2% free 9811K/9964K, paused 24ms, total 24ms
04-07 23:25:31.870: I/dalvikvm-heap(819): Grow heap (frag case) to 16.408MB for 7077904-byte allocation
04-07 23:25:31.950: D/dalvikvm(819): GC_FOR_ALLOC freed <1K, 1% free 16723K/16880K, paused 78ms, total 78ms
04-07 23:25:32.900: D/(819): HostConnection::get() New Host Connection established 0xb860aab0, tid 819
04-07 23:25:33.070: W/EGL_emulation(819): eglSurfaceAttrib not implemented
04-07 23:25:33.090: D/OpenGLRenderer(819): Enabling debug mode 0
04-07 23:26:37.049: D/dalvikvm(1073): GC_FOR_ALLOC freed 54K, 5% free 2900K/3040K, paused 34ms, total 38ms
04-07 23:26:37.049: I/dalvikvm-heap(1073): Grow heap (frag case) to 9.659MB for 7077904-byte allocation
04-07 23:26:37.089: D/dalvikvm(1073): GC_FOR_ALLOC freed 2K, 2% free 9810K/9956K, paused 34ms, total 34ms
04-07 23:26:38.059: D/dalvikvm(1073): GC_FOR_ALLOC freed <1K, 2% free 9811K/9956K, paused 22ms, total 23ms
04-07 23:26:38.059: I/dalvikvm-heap(1073): Grow heap (frag case) to 16.408MB for 7077904-byte allocation
04-07 23:26:38.109: D/dalvikvm(1073): GC_FOR_ALLOC freed <1K, 1% free 16723K/16872K, paused 40ms, total 40ms
04-07 23:26:38.859: D/(1073): HostConnection::get() New Host Connection established 0xb860aac8, tid 1073
04-07 23:26:39.019: W/EGL_emulation(1073): eglSurfaceAttrib not implemented
04-07 23:26:39.049: D/OpenGLRenderer(1073): Enabling debug mode 0
04-07 23:26:40.159: I/Choreographer(1073): Skipped 44 frames! The application may be doing too much work on its main thread.
04-07 23:26:41.959: D/AndroidRuntime(1073): Shutting down VM
04-07 23:26:41.959: W/dalvikvm(1073): threadid=1: thread exiting with uncaught exception (group=0xb3a2dba8)
04-07 23:26:41.979: E/AndroidRuntime(1073): FATAL EXCEPTION: main
04-07 23:26:41.979: E/AndroidRuntime(1073): Process: ca.mohawk.you.lab6a, PID: 1073
04-07 23:26:41.979: E/AndroidRuntime(1073): java.lang.IllegalStateException: Could not find a method crossfade(View) in the activity class ca.mohawk.you.lab6a.MainActivity for onClick handler on view class android.widget.Button with id 'button'
04-07 23:26:41.979: E/AndroidRuntime(1073): at android.view.View$1.onClick(View.java:3810)
04-07 23:26:41.979: E/AndroidRuntime(1073): at android.view.View.performClick(View.java:4438)
04-07 23:26:41.979: E/AndroidRuntime(1073): at android.view.View$PerformClick.run(View.java:18422)
04-07 23:26:41.979: E/AndroidRuntime(1073): at android.os.Handler.handleCallback(Handler.java:733)
04-07 23:26:41.979: E/AndroidRuntime(1073): at android.os.Handler.dispatchMessage(Handler.java:95)
04-07 23:26:41.979: E/AndroidRuntime(1073): at android.os.Looper.loop(Looper.java:136)
04-07 23:26:41.979: E/AndroidRuntime(1073): at android.app.ActivityThread.main(ActivityThread.java:5017)
04-07 23:26:41.979: E/AndroidRuntime(1073): at java.lang.reflect.Method.invokeNative(Native Method)
04-07 23:26:41.979: E/AndroidRuntime(1073): at java.lang.reflect.Method.invoke(Method.java:515)
04-07 23:26:41.979: E/AndroidRuntime(1073): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779)
04-07 23:26:41.979: E/AndroidRuntime(1073): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595)
04-07 23:26:41.979: E/AndroidRuntime(1073): at dalvik.system.NativeStart.main(Native Method)
04-07 23:26:41.979: E/AndroidRuntime(1073): Caused by: java.lang.NoSuchMethodException: crossfade [class android.view.View]
04-07 23:26:41.979: E/AndroidRuntime(1073): at java.lang.Class.getConstructorOrMethod(Class.java:472)
04-07 23:26:41.979: E/AndroidRuntime(1073): at java.lang.Class.getMethod(Class.java:857)
04-07 23:26:41.979: E/AndroidRuntime(1073): at android.view.View$1.onClick(View.java:3803)
04-07 23:26:41.979: E/AndroidRuntime(1073): ... 11 more
04-07 23:26:46.359: I/Process(1073): Sending signal. PID: 1073 SIG: 9
04-07 23:28:55.859: D/dalvikvm(1126): GC_FOR_ALLOC freed 58K, 5% free 2900K/3044K, paused 36ms, total 38ms
04-07 23:28:55.859: I/dalvikvm-heap(1126): Grow heap (frag case) to 9.659MB for 7077904-byte allocation
04-07 23:28:55.909: D/dalvikvm(1126): GC_FOR_ALLOC freed 2K, 2% free 9810K/9960K, paused 43ms, total 43ms
04-07 23:28:56.779: D/dalvikvm(1126): GC_FOR_ALLOC freed <1K, 2% free 9811K/9960K, paused 22ms, total 22ms
04-07 23:28:56.779: I/dalvikvm-heap(1126): Grow heap (frag case) to 16.408MB for 7077904-byte allocation
04-07 23:28:56.839: D/dalvikvm(1126): GC_FOR_ALLOC freed <1K, 1% free 16723K/16876K, paused 50ms, total 50ms
04-07 23:28:57.539: D/(1126): HostConnection::get() New Host Connection established 0xb876ca90, tid 1126
04-07 23:28:57.629: W/EGL_emulation(1126): eglSurfaceAttrib not implemented
04-07 23:28:57.639: D/OpenGLRenderer(1126): Enabling debug mode 0
04-07 23:29:00.669: D/AndroidRuntime(1126): Shutting down VM
04-07 23:29:00.679: W/dalvikvm(1126): threadid=1: thread exiting with uncaught exception (group=0xb3a2dba8)
04-07 23:29:00.699: E/AndroidRuntime(1126): FATAL EXCEPTION: main
04-07 23:29:00.699: E/AndroidRuntime(1126): Process: ca.mohawk.you.lab6a, PID: 1126
04-07 23:29:00.699: E/AndroidRuntime(1126): java.lang.IllegalStateException: Could not find a method crossfade(View) in the activity class ca.mohawk.you.lab6a.MainActivity for onClick handler on view class android.widget.Button with id 'button'
04-07 23:29:00.699: E/AndroidRuntime(1126): at android.view.View$1.onClick(View.java:3810)
04-07 23:29:00.699: E/AndroidRuntime(1126): at android.view.View.performClick(View.java:4438)
04-07 23:29:00.699: E/AndroidRuntime(1126): at android.view.View$PerformClick.run(View.java:18422)
04-07 23:29:00.699: E/AndroidRuntime(1126): at android.os.Handler.handleCallback(Handler.java:733)
04-07 23:29:00.699: E/AndroidRuntime(1126): at android.os.Handler.dispatchMessage(Handler.java:95)
04-07 23:29:00.699: E/AndroidRuntime(1126): at android.os.Looper.loop(Looper.java:136)
04-07 23:29:00.699: E/AndroidRuntime(1126): at android.app.ActivityThread.main(ActivityThread.java:5017)
04-07 23:29:00.699: E/AndroidRuntime(1126): at java.lang.reflect.Method.invokeNative(Native Method)
04-07 23:29:00.699: E/AndroidRuntime(1126): at java.lang.reflect.Method.invoke(Method.java:515)
04-07 23:29:00.699: E/AndroidRuntime(1126): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779)
04-07 23:29:00.699: E/AndroidRuntime(1126): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595)
04-07 23:29:00.699: E/AndroidRuntime(1126): at dalvik.system.NativeStart.main(Native Method)
04-07 23:29:00.699: E/AndroidRuntime(1126): Caused by: java.lang.NoSuchMethodException: crossfade [class android.view.View]
04-07 23:29:00.699: E/AndroidRuntime(1126): at java.lang.Class.getConstructorOrMethod(Class.java:472)
04-07 23:29:00.699: E/AndroidRuntime(1126): at java.lang.Class.getMethod(Class.java:857)
04-07 23:29:00.699: E/AndroidRuntime(1126): at android.view.View$1.onClick(View.java:3803)
04-07 23:29:00.699: E/AndroidRuntime(1126): ... 11 more
04-07 23:34:46.919: D/dalvikvm(1179): GC_FOR_ALLOC freed 61K, 5% free 2902K/3044K, paused 35ms, total 37ms
04-07 23:34:46.919: I/dalvikvm-heap(1179): Grow heap (frag case) to 9.660MB for 7077904-byte allocation
04-07 23:34:46.959: D/dalvikvm(1179): GC_FOR_ALLOC freed 2K, 2% free 9811K/9960K, paused 31ms, total 31ms
04-07 23:34:47.839: D/dalvikvm(1179): GC_FOR_ALLOC freed <1K, 2% free 9814K/9960K, paused 21ms, total 22ms
04-07 23:34:47.839: I/dalvikvm-heap(1179): Grow heap (frag case) to 16.410MB for 7077904-byte allocation
04-07 23:34:47.889: D/dalvikvm(1179): GC_FOR_ALLOC freed <1K, 1% free 16725K/16876K, paused 40ms, total 41ms
04-07 23:34:48.579: D/(1179): HostConnection::get() New Host Connection established 0xb87602e8, tid 1179
04-07 23:34:48.689: W/EGL_emulation(1179): eglSurfaceAttrib not implemented
04-07 23:34:48.699: D/OpenGLRenderer(1179): Enabling debug mode 0
04-07 23:35:00.309: D/AndroidRuntime(1179): Shutting down VM
04-07 23:35:00.319: W/dalvikvm(1179): threadid=1: thread exiting with uncaught exception (group=0xb3a2dba8)
04-07 23:35:00.349: E/AndroidRuntime(1179): FATAL EXCEPTION: main
04-07 23:35:00.349: E/AndroidRuntime(1179): Process: ca.mohawk.you.lab6a, PID: 1179
04-07 23:35:00.349: E/AndroidRuntime(1179): java.lang.IllegalStateException: Could not find a method crossfade(View) in the activity class ca.mohawk.you.lab6a.MainActivity for onClick handler on view class android.widget.Button with id 'button'
04-07 23:35:00.349: E/AndroidRuntime(1179): at android.view.View$1.onClick(View.java:3810)
04-07 23:35:00.349: E/AndroidRuntime(1179): at android.view.View.performClick(View.java:4438)
04-07 23:35:00.349: E/AndroidRuntime(1179): at android.view.View$PerformClick.run(View.java:18422)
04-07 23:35:00.349: E/AndroidRuntime(1179): at android.os.Handler.handleCallback(Handler.java:733)
04-07 23:35:00.349: E/AndroidRuntime(1179): at android.os.Handler.dispatchMessage(Handler.java:95)
04-07 23:35:00.349: E/AndroidRuntime(1179): at android.os.Looper.loop(Looper.java:136)
04-07 23:35:00.349: E/AndroidRuntime(1179): at android.app.ActivityThread.main(ActivityThread.java:5017)
04-07 23:35:00.349: E/AndroidRuntime(1179): at java.lang.reflect.Method.invokeNative(Native Method)
04-07 23:35:00.349: E/AndroidRuntime(1179): at java.lang.reflect.Method.invoke(Method.java:515)
04-07 23:35:00.349: E/AndroidRuntime(1179): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779)
04-07 23:35:00.349: E/AndroidRuntime(1179): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595)
04-07 23:35:00.349: E/AndroidRuntime(1179): at dalvik.system.NativeStart.main(Native Method)
04-07 23:35:00.349: E/AndroidRuntime(1179): Caused by: java.lang.NoSuchMethodException: crossfade [class android.view.View]
04-07 23:35:00.349: E/AndroidRuntime(1179): at java.lang.Class.getConstructorOrMethod(Class.java:472)
04-07 23:35:00.349: E/AndroidRuntime(1179): at java.lang.Class.getMethod(Class.java:857)
04-07 23:35:00.349: E/AndroidRuntime(1179): at android.view.View$1.onClick(View.java:3803)
04-07 23:35:00.349: E/AndroidRuntime(1179): ... 11 more
04-07 23:35:03.109: I/Process(1179): Sending signal. PID: 1179 SIG: 9
04-07 23:35:36.759: D/dalvikvm(1221): GC_FOR_ALLOC freed 65K, 5% free 2902K/3048K, paused 38ms, total 40ms
04-07 23:35:36.769: I/dalvikvm-heap(1221): Grow heap (frag case) to 9.660MB for 7077904-byte allocation
04-07 23:35:36.839: D/dalvikvm(1221): GC_FOR_ALLOC freed 2K, 2% free 9811K/9964K, paused 68ms, total 68ms
04-07 23:35:37.799: D/dalvikvm(1221): GC_FOR_ALLOC freed <1K, 2% free 9814K/9964K, paused 23ms, total 23ms
04-07 23:35:37.799: I/dalvikvm-heap(1221): Grow heap (frag case) to 16.411MB for 7077904-byte allocation
04-07 23:35:37.859: D/dalvikvm(1221): GC_FOR_ALLOC freed <1K, 1% free 16725K/16880K, paused 47ms, total 47ms
04-07 23:35:38.599: D/(1221): HostConnection::get() New Host Connection established 0xb8738680, tid 1221
04-07 23:35:38.749: W/EGL_emulation(1221): eglSurfaceAttrib not implemented
04-07 23:35:38.769: D/OpenGLRenderer(1221): Enabling debug mode 0
04-07 23:35:42.339: D/AndroidRuntime(1221): Shutting down VM
04-07 23:35:42.339: W/dalvikvm(1221): threadid=1: thread exiting with uncaught exception (group=0xb3a2dba8)
04-07 23:35:42.409: E/AndroidRuntime(1221): FATAL EXCEPTION: main
04-07 23:35:42.409: E/AndroidRuntime(1221): Process: ca.mohawk.you.lab6a, PID: 1221
04-07 23:35:42.409: E/AndroidRuntime(1221): java.lang.IllegalStateException: Could not find a method crossfade(View) in the activity class ca.mohawk.you.lab6a.MainActivity for onClick handler on view class android.widget.Button with id 'button'
04-07 23:35:42.409: E/AndroidRuntime(1221): at android.view.View$1.onClick(View.java:3810)
04-07 23:35:42.409: E/AndroidRuntime(1221): at android.view.View.performClick(View.java:4438)
04-07 23:35:42.409: E/AndroidRuntime(1221): at android.view.View$PerformClick.run(View.java:18422)
04-07 23:35:42.409: E/AndroidRuntime(1221): at android.os.Handler.handleCallback(Handler.java:733)
04-07 23:35:42.409: E/AndroidRuntime(1221): at android.os.Handler.dispatchMessage(Handler.java:95)
04-07 23:35:42.409: E/AndroidRuntime(1221): at android.os.Looper.loop(Looper.java:136)
04-07 23:35:42.409: E/AndroidRuntime(1221): at android.app.ActivityThread.main(ActivityThread.java:5017)
04-07 23:35:42.409: E/AndroidRuntime(1221): at java.lang.reflect.Method.invokeNative(Native Method)
04-07 23:35:42.409: E/AndroidRuntime(1221): at java.lang.reflect.Method.invoke(Method.java:515)
04-07 23:35:42.409: E/AndroidRuntime(1221): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779)
04-07 23:35:42.409: E/AndroidRuntime(1221): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595)
04-07 23:35:42.409: E/AndroidRuntime(1221): at dalvik.system.NativeStart.main(Native Method)
04-07 23:35:42.409: E/AndroidRuntime(1221): Caused by: java.lang.NoSuchMethodException: crossfade [class android.view.View]
04-07 23:35:42.409: E/AndroidRuntime(1221): at java.lang.Class.getConstructorOrMethod(Class.java:472)
04-07 23:35:42.409: E/AndroidRuntime(1221): at java.lang.Class.getMethod(Class.java:857)
04-07 23:35:42.409: E/AndroidRuntime(1221): at android.view.View$1.onClick(View.java:3803)
04-07 23:35:42.409: E/AndroidRuntime(1221): ... 11 more
04-07 23:35:44.729: I/Process(1221): Sending signal. PID: 1221 SIG: 9
回答1:
When you declare the onClick attribute in xml, the corresponding method in the Java code needs to have a certain signature. Change:
private void crossfade()
to:
public void crossfade(View v)
来源：https://stackoverflow.com/questions/22927123/crossfading-2-views-using-a-button-in-android