今天，我们要讲的是Android里的手势，为了方便理解，我们做了一个dome
用左滑右滑的手势实现的图片的切换
效果如下：
废话不多说，我们直接上代码
package com.example.myas_020; import android.support.v7.app.AppCompatActivity; import android.os.Bundle; import android.util.Log; import android.view.GestureDetector; import android.view.MotionEvent; import android.widget.ImageView; import android.widget.Toast; import android.widget.ViewFlipper; public class MainActivity extends AppCompatActivity { private ViewFlipper vf_main_image; private int images[]={R.drawable.s1,R.drawable.s2,R.drawable.s3}; private GestureDetector gd; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); vf_main_image = (ViewFlipper) findViewById(R.id.vf_main_image); for (int i = 0; i <images.length ; i++) { ImageView iv=new ImageView(this); iv.setImageResource(images[i]); vf_main_image.addView(iv); } //实例化手势检测器类 gd = new GestureDetector(this, new GestureDetector.OnGestureListener() { //按下 @Override public boolean onDown(MotionEvent e) { return false; } //按下，但是还未抬起 @Override public void onShowPress(MotionEvent e) { } //轻按，按一下，立刻抬起 @Override public boolean onSingleTapUp(MotionEvent e) { return false; } //滚动 @Override public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX, float distanceY) { return false; } //长按 @Override public void onLongPress(MotionEvent e) { } //拖动 @Override public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY) { if(e2.getX()-e1.getX()>200){ Toast.makeText(MainActivity.this, "右滑,上一张", Toast.LENGTH_SHORT).show(); vf_main_image.showPrevious(); //左进右出 vf_main_image.setInAnimation(MainActivity.this,R.anim.left_in); vf_main_image.setOutAnimation(MainActivity.this,R.anim.right_out); }if(e1.getX()-e2.getX()>200){ Toast.makeText(MainActivity.this, "左滑,下一张", Toast.LENGTH_SHORT).show(); vf_main_image.showNext(); //左出右进 vf_main_image.setInAnimation(MainActivity.this,R.anim.right_in); vf_main_image.setOutAnimation(MainActivity.this,R.anim.left_out); } return false; } }); } @Override public boolean onTouchEvent(MotionEvent event) { return gd.onTouchEvent(event); } }
还有四个动画的代码：
左滑进
<?xml version="1.0" encoding="utf-8"?> <set xmlns:android="http://schemas.android.com/apk/res/android" android:fillAfter="true" android:duration="1500" > <translate android:fromXDelta="-100%p" android:toXDelta="0" ></translate> <rotate android:fromDegrees="0" android:toDegrees="360" android:pivotX="100%" android:pivotY="50%" ></rotate> </set>
左滑出
<?xml version="1.0" encoding="utf-8"?> <set xmlns:android="http://schemas.android.com/apk/res/android" android:fillAfter="true" android:duration="1500" > <translate android:fromXDelta="0" android:toXDelta="100%p" ></translate> <rotate android:fromDegrees="0" android:toDegrees="360" android:pivotX="0" android:pivotY="50%" ></rotate> </set>右滑进
<?xml version="1.0" encoding="utf-8"?> <set xmlns:android="http://schemas.android.com/apk/res/android" android:fillAfter="true" android:duration="1500" > <translate android:fromXDelta="100%p" android:toXDelta="0" ></translate> <rotate android:fromDegrees="0" android:toDegrees="360" android:pivotX="100%" android:pivotY="50%" ></rotate> </set>
右滑出
<?xml version="1.0" encoding="utf-8"?> <set xmlns:android="http://schemas.android.com/apk/res/android" android:fillAfter="true" android:duration="1500" > <translate android:fromXDelta="0" android:toXDelta="-100%p" ></translate> <rotate android:fromDegrees="0" android:toDegrees="360" android:pivotX="0" android:pivotY="50%" ></rotate> </set>
