问题
My activity displays images and i want to display two buttons when the user touch the screen, and to disappear these button on next touch.
My activity file ImageViewPager.java is as follows:
package com.pankajvatsa.testfeet;
import java.util.ArrayList;
import java.util.List;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.support.v4.view.ViewPager;
import android.view.MotionEvent;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.RelativeLayout;
public class ImageViewPager extends Activity {
// Declare Variable
int position;
Button bWallpaperButton;
Button bDownloadButton;
RelativeLayout mainLay;
int flagForButton = 0;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// Set title for the ViewPager
setTitle("ViewPager");
// Get the view from view_pager.xml
setContentView(R.layout.activity_image_view_pager);
mainLay = (RelativeLayout) findViewById(R.id.rl_view_pager);
mainLay.setOnTouchListener(new View.OnTouchListener() {
@Override
public boolean onTouch(View v, MotionEvent event) {
// TODO Auto-generated method stub
if (event.getAction() == MotionEvent.ACTION_DOWN) {
bWallpaperButton.setVisibility(View.VISIBLE);
bDownloadButton.setVisibility(View.VISIBLE);
return true;
}
if (event.getAction() == MotionEvent.ACTION_UP) {
bWallpaperButton.setVisibility(View.INVISIBLE);
bDownloadButton.setVisibility(View.INVISIBLE);
return true;
}
return true;
}
});
bWallpaperButton = (Button) findViewById(R.id.bSetWallpaper);
bDownloadButton = (Button) findViewById(R.id.bSaveToGallery);
// Retrieve data from MainActivity on item click event
Intent p = getIntent();
position = p.getExtras().getInt("id");
ImageAdapter imageAdapter = new ImageAdapter(this);
List<ImageView> images = new ArrayList<ImageView>();
// Retrieve all the images
for (int i = 0; i < imageAdapter.getCount(); i++) {
ImageView imageView = new ImageView(this);
imageView.setImageResource(imageAdapter.mThumbIds[i]);
imageView.setScaleType(ImageView.ScaleType.CENTER);
images.add(imageView);
}
// Set the images into ViewPager
ImagePagerAdapter pageradapter = new ImagePagerAdapter(images);
ViewPager viewpager = (ViewPager) findViewById(R.id.image_pager);
viewpager.setAdapter(pageradapter);
// Show images following the position
viewpager.setCurrentItem(position);
}
}
And my xml file is as follows:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/rl_view_pager"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:clickable="true"
android:focusable="true"
android:focusableInTouchMode="true" >
<android.support.v4.view.ViewPager
android:id="@+id/image_pager"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:clickable="true"
android:focusable="true"
android:focusableInTouchMode="true" >
</android.support.v4.view.ViewPager>
<Button
android:id="@+id/bSetWallpaper"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_alignParentRight="true"
android:text="@string/set_wallpaper"
android:visibility="gone" />
<Button
android:id="@+id/bSaveToGallery"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_alignParentLeft="true"
android:text="@string/save_local"
android:visibility="gone" />
</RelativeLayout>
回答1:
Here is an example using LinearLayout but should work fine with RelativeLayout as well:
Button btn1;
boolean gone = false;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
btn1 = (Button)findViewById(R.id.button1);
LinearLayout ln = (LinearLayout)findViewById(R.id.LinearLayout01);
ln.setOnTouchListener(new View.OnTouchListener() {
@Override
public boolean onTouch(View view, MotionEvent motionEvent) {
if(motionEvent.getAction() == MotionEvent.ACTION_DOWN){
if(!gone){
btn1.setVisibility(View.GONE);
gone = true;
}else{
btn1.setVisibility(View.VISIBLE);
gone = false;
}
}
return true;
}
});
}
回答2:
Well, it somehow worked on removing the setOnTouchListener() from layout and adding it on the ViewPager. My Updated code(with other changes for differentiating tap and swipe) is:
package com.pankajvatsa.testfeet;
import java.util.ArrayList;
import java.util.List;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.support.v4.view.ViewPager;
import android.view.MotionEvent;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.RelativeLayout;
public class ImageViewPager extends Activity {
// Declare Variable
int position;
Button bWallpaperButton;
Button bDownloadButton;
RelativeLayout mainLay;
int flagForButton = 0;
boolean gone = false;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// Set title for the ViewPager
setTitle("ViewPager");
// Get the view from view_pager.xml
setContentView(R.layout.activity_image_view_pager);
bWallpaperButton = (Button) findViewById(R.id.bSetWallpaper);
bDownloadButton = (Button) findViewById(R.id.bSaveToGallery);
mainLay = (RelativeLayout) findViewById(R.id.rl_view_pager);
// Retrieve data from MainActivity on item click event
Intent p = getIntent();
position = p.getExtras().getInt("id");
ImageAdapter imageAdapter = new ImageAdapter(this);
List<ImageView> images = new ArrayList<ImageView>();
// Retrieve all the images
for (int i = 0; i < imageAdapter.getCount(); i++) {
ImageView imageView = new ImageView(this);
imageView.setImageResource(imageAdapter.mThumbIds[i]);
imageView.setScaleType(ImageView.ScaleType.CENTER);
images.add(imageView);
}
// Set the images into ViewPager
ImagePagerAdapter pageradapter = new ImagePagerAdapter(images);
ViewPager viewpager = (ViewPager) findViewById(R.id.image_pager);
viewpager.setAdapter(pageradapter);
// Show images following the position
viewpager.setCurrentItem(position);
viewpager.setOnTouchListener(new View.OnTouchListener() {
private float pointX;
private float pointY;
private int tolerance = 50;
@Override
public boolean onTouch(View v, MotionEvent event) {
// TODO Auto-generated method stub
switch (event.getAction()) {
case MotionEvent.ACTION_MOVE:
return false;
case MotionEvent.ACTION_DOWN:
pointX = event.getX();
pointY = event.getY();
break;
case MotionEvent.ACTION_UP:
boolean sameX = pointX + tolerance > event.getX() && pointX - tolerance < event.getX();
boolean sameY = pointY + tolerance > event.getY() && pointY - tolerance < event.getY();
if(sameX && sameY){
//The user "clicked" certain point in the screen or just returned to the same position an raised the finger
if(gone == false){
bWallpaperButton.setVisibility(View.GONE);
bDownloadButton.setVisibility(View.GONE);
gone = true;
}else{
bWallpaperButton.setVisibility(View.VISIBLE);
bDownloadButton.setVisibility(View.VISIBLE);
gone = false;
}
}
}
return false;
}
});
}
}
来源：https://stackoverflow.com/questions/17474384/how-to-hide-and-show-buttons-on-alternate-touch-events