双击放大图片 手指移动图片位置
手指脱动图片 双击放大
package com.softpo.pointerstouchevent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.GestureDetector;
import android.view.MotionEvent;
import com.softpo.pointerstouchevent.widget.CustomImage;
public class MainActivity extends AppCompatActivity implements GestureDetector.OnGestureListener, GestureDetector.OnDoubleTapListener {
private CustomImage mImage;
//手势识别：按下，抬起，长按，双击……
private GestureDetector mGestureDetector;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mImage = (CustomImage) findViewById(R.id.image);
mGestureDetector = new GestureDetector(this,this);
mGestureDetector.setOnDoubleTapListener(this);
}
//屏幕上的触摸事件，Activity捕获到
@Override
public boolean onTouchEvent(MotionEvent event) {
//通过event获取屏幕上手指个数
int pointerCount = event.getPointerCount();
switch (pointerCount){
case 1://移动图片
mImage.move(event);
break;
case 2://缩放
mImage.scale(event);
break;
}
return mGestureDetector.onTouchEvent(event);
}
@Override
public boolean onDown(MotionEvent e) {
Log.d("flag", "----------------->onDown: 手指按下");
return false;
}
@Override
public void onShowPress(MotionEvent e) {
Log.d("flag", "----------------->onShowPress: 手指按下，长安之前" );
}
@Override
public boolean onSingleTapUp(MotionEvent e) {
Log.d("flag", "----------------->onSingleTapUp: 单击抬起事件");
return false;
}
@Override
public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX, float distanceY) {
Log.d("flag", "----------------->onScroll: 手指在屏幕上滑动");
return false;
}
@Override
public void onLongPress(MotionEvent e) {
Log.d("flag", "----------------->onLongPress: 长按");
}
@Override
public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY) {
Log.d("flag", "----------------->onFling: 手指离开屏幕惯性滑动");
float e1X = e1.getX();
float e2X = e2.getX();
// if(e1X-e2X>10){//向左移动
// //缩小图片
// mImage.scaleImage(0);
// }else if(e1X-e2X<-10){//向右移动
// //放大图片
// mImage.scaleImage(1);
// }
return false;
}
@Override
public boolean onSingleTapConfirmed(MotionEvent e) {
Log.d("flag", "----------------->onSingleTapConfirmed: 单击确定事件，两次单击时间间隔长了点");
return false;
}
@Override
public boolean onDoubleTap(MotionEvent e) {
Log.d("flag", "----------------->onDoubleTap: 双击事件");
mImage.scaleImage(1);//图片放大
return false;
}
@Override
public boolean onDoubleTapEvent(MotionEvent e) {
Log.d("flag", "----------------->onDoubleTapEvent: 双击发生的之间的事件" );
return false;
}
}
package com.softpo.pointerstouchevent.widget;
import android.content.Context;
import android.util.AttributeSet;
import android.util.Log;
import android.view.MotionEvent;
import android.widget.ImageView;
/**
* Created by softpo on 2017/4/26.
* Email: [email protected]
*/
public class CustomImage extends ImageView {
//记录上一次的位置
private float last_X = 0;
private float last_Y = 0;
public CustomImage(Context context, AttributeSet attrs) {
super(context, attrs);
}
//手指移动，更新图片的位置
public void move(MotionEvent event) {
// Log.d("flag", "----------------->move: " +current_X+", "+current_Y);
switch (event.getAction()){
case MotionEvent.ACTION_DOWN:
Log.d("flag", "----------------->move: down");
last_X = event.getX();
last_Y = event.getY();
break;
case MotionEvent.ACTION_MOVE:
Log.d("flag", "----------------->move: move");
//当前的坐标
float current_X = event.getX();//x轴坐标
float current_Y = event.getY();//Y轴坐标
float abs_x = Math.abs(current_X - last_X);
float abs_y = Math.abs(current_Y - last_Y);
if(abs_x>10&&abs_x<40||abs_y>10&&abs_y<40){
moveImage(current_X-last_X,current_Y-last_Y);
}
last_X = event.getX();
last_Y = event.getY();
break;
}
}
private void moveImage(float x, float y) {
int offsetX = (int) x;
int offsetY = (int) y;
this.setFrame(getLeft()+offsetX,getTop()+offsetY,getRight()+offsetX,getBottom()+offsetY);
}
private float scaleSize = 0.1f;//缩放比例
private double last_gap = 0;//两点之间的距离
public void scale(MotionEvent event) {
switch (event.getAction()){
case MotionEvent.ACTION_MOVE:
float x0 = event.getX(0);
float x1 = event.getX(1);
float y0 = event.getY(0);
float y1 = event.getY(1);
double current_gap = Math.sqrt((x0 - x1) * (x0 - x1) + (y0 - y1) * (y0 - y1));
if(current_gap-last_gap>10){//两点之间的距离变大
scaleImage(1);
}else if(current_gap - last_gap<-10){//两点之间距离变小
scaleImage(0);
}
last_gap = current_gap;
break;
}
}
public void scaleImage(int flag) {
int scaleSize_X = (int) (scaleSize * getWidth());
int scaleSize_Y = (int) (scaleSize*getHeight());
switch (flag){
case 0://缩小
if(getWidth()>50+scaleSize_X*2)//其小有形
this.setFrame(
getLeft()+ scaleSize_X,
getTop()+scaleSize_Y,
getRight()-scaleSize_X,
getBottom()-scaleSize_Y);
break;
case 1://放大
//其大有边
if(getWidth()
getTop()-scaleSize_Y,
getRight()+scaleSize_X,
getBottom()+scaleSize_Y);
}
break;
}
}
}