问题
Hi I have a button in xml, and I am using OnTouchListener in my activity to get button press and release. But the problem is that when I press the button the background color is not changing. Where as when I extend may activity with OnClickListener the background is changing. Can any one tell what wrong with my code.
public class pushbuttonActivity extends Activity implements OnTouchListener {
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.push_button_layout);
GPIO_0_B = (Button) findViewById(R.id.GPIO_0);
GPIO_0_B.setOnTouchListener((OnTouchListener) this);
}
public boolean onTouch(View v,MotionEvent event) {
switch(v.getId()) {
case R.id.GPIO_0 : GPIOPORT=0;
break;
default : break;
}
if(event.getAction() == MotionEvent.ACTION_DOWN) {
//Do something on touch
} else if (event.getAction() == MotionEvent.ACTION_UP) {
//Do something in release
}
return true;
}
push_button_layout.xml
<RelativeLayout .........
.................
<Button
android:id="@+id/GPIO_0"
android:layout_width="80dp"
android:layout_height="80dp"
android:background="@drawable/round_button"
android:textStyle="bold"
android:textSize="14sp"
android:text="GPIO 0"
android:layout_marginTop="15dp"
android:layout_marginBottom="10dp"
android:layout_marginLeft="50dp"
/>
round_button.xml
<?xml version="1.0" encoding="utf-8" ?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<!-- Non focused states
-->
<item android:state_focused="false" android:state_selected="false" android:state_pressed="false" android:drawable="@drawable/round_button_unfocused" />
<item android:state_focused="false" android:state_selected="true" android:state_pressed="false" android:drawable="@drawable/round_button_unfocused" />
<!-- Focused states
-->
<item android:state_focused="true" android:state_selected="false" android:state_pressed="false" android:drawable="@drawable/round_button_focus" />
<item android:state_focused="true" android:state_selected="true" android:state_pressed="false" android:drawable="@drawable/round_button_focus" />
<!-- Pressed
-->
<item android:state_pressed="true" android:drawable="@drawable/round_button_press" />
</selector>
round_button_focus.xml
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="rectangle">
<stroke
android:width="1dp"
android:color="#FF404040" />
<corners
android:radius="6dp" />
<size android:height="40dp"
android:width="40dp"/>
<gradient
android:startColor="#FF6800"
android:centerColor="#FF8000"
android:endColor="#FF9700"
android:angle="90" />
</shape>
round_button_press.xml
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="rectangle">
<stroke
android:width="2dp"
android:color="#FF606060" />
<corners
android:radius="40dp" />
<gradient
android:startColor="#FF0000"
android:centerColor="#FF0000"
android:endColor="#FF0000"
android:angle="90" />
</shape>
round_button_unfocus.xml
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="rectangle">
<stroke
android:width="2dp"
android:color="#FF606060" />
<corners
android:radius="40dp" />
<gradient
android:startColor="#550000"
android:centerColor="#550000"
android:endColor="#550000"
android:angle="90" />
</shape>
And sorry for the lengthy post....
回答1:
Using Ontouch you wont get the Clicked state of your button
use Onclick Coz , In onclick method Pressed state of button will be true
Actually I need to get button click and release
use this to get click and release
GPIO_0_B.setOnClickListener(new OnClickListener() {
@Override
public boolean onTouch(View v, MotionEvent event)
{
if(event.getAction() == MotionEvent.ACTION_DOWN) {
GPIO_0_B.setBackground(R.drawable.round_button_focus);
} else if (event.getAction() == MotionEvent.ACTION_UP) {
GPIO_0_B.setBackground(R.drawable.round_button_unfocused);
}
}
};
For touch listner change this line GPIO_0_B.setOnClickListener(new OnClickListener() {
to
GPIO_0_B.setOnTouchListener(new OnTouchListener() {
how can I do with its id, Actually I have more than one button
Do this in onCreate():
{
Button GPIO_0_B1 =(Button) findViewById(R.id.youridfromxml);
Button GPIO_0_B1 =(Button) findViewById(R.id.youridfromxml);
GPIO_0_B1.setOnClickListener(getOnClickDoSomething(GPIO_0_B1);
GPIO_0_B2.setOnClickListener(getOnClickDoSomething(GPIO_0_B2);
}
Now
create new method (outside oncreate() method:- info for noobs)
View.OnClickListener getOnClickDoSomething(final Button Gpbot)
{
return new View.OnClickListener()
{
@Override
public void onClick(View v)
{
if(event.getAction() == MotionEvent.ACTION_DOWN) {
Gpbot.setBackground(R.drawable.round_button_focus);
} else if (event.getAction() == MotionEvent.ACTION_UP) {
Gpbot.setBackground(R.drawable.round_button_unfocused);
}
}
}
}
回答2:
Just setting a layout as a background to your Button in xml will do the trick. have a xml in your drawable folder named for eg:clickedstate.xml like this
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item android:state_enabled="false"
android:drawable="@drawable/default_bgnd" />
<item android:state_focused="true"
android:drawable="@drawable/new_green" />
<item android:state_pressed="true"
android:drawable="@drawable/new_green" />
<item android:state_checked="true"
android:drawable="@drawable/new_green"/>
<item android:state_selected="true"
android:drawable="@drawable/new_green" />
</selector>
In your xml just do this for your button
android:background="@drawable/clickedstate"
回答3:
@Override
public boolean onTouch(View v, MotionEvent event) {
switch(event.getAction()) {
case MotionEvent.ACTION_DOWN:
v.setPressed(true);
//doYourWorkHere();
break;
case MotionEvent.ACTION_UP:
v.setPressed(false);
//doYourWorkHere();
break;
}
return true;/* true to deactivate other listeners at the same time; false otherwise */
}
回答4:
You can use the below code through the onclick event listener to achieve this :
StateListDrawable states = new StateListDrawable();
Drawable image_normal = //drawable of the image
Drawable image_focused = //drawable of the image
Drawable image_pressed = //drawable of the image
states.addState(new int[] {android.R.attr.state_pressed},image_focused);
states.addState(new int[] {android.R.attr.state_focused},image_pressed);
states.addState(new int[] { },image_normal);
buttonObj.setBackgroundDrawable(states);
回答5:
Try with this code.
@Override
public boolean onTouch(View view, MotionEvent event) {
view.setSelected(true);
...
return true;
}
来源：https://stackoverflow.com/questions/18848475/android-how-to-change-button-background-on-ontouchlistener