public class MainActivity extends Activity {
private Button but;
private Button but1;
private ImageView img;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
but=(Button)findViewById(R.id.but);
but1=(Button)findViewById(R.id.but1);
img=(ImageView)findViewById(R.id.img);

    but.setOnClickListener(new OnClickListener() {
        
        @Override
        public void onClick(View v) {
            // TODO Auto-generated method stub
            showPop(v);
        }
    });
    but1.setOnClickListener(new OnClickListener() {
        
        @Override
        public void onClick(View v) {
            // TODO Auto-generated method stub
            show1(v);
        }
    });
}
private void showPop(View v){
    View pv=View.inflate(this, R.layout.popwindow, null);
    TextView tv1=(TextView)pv.findViewById(R.id.tv1);
    final PopupWindow pop=new PopupWindow(pv, LayoutParams.MATCH_PARENT,LayoutParams.WRAP_CONTENT);
    
    pop.setOutsideTouchable(true);
    pop.setBackgroundDrawable(new ColorDrawable(0x00000000));
    
    pop.setFocusable(true);
    tv1.setOnClickListener(new OnClickListener() {
        
        @Override
        public void onClick(View v) {
            // TODO Auto-generated method stub
            Toast.makeText(MainActivity.this, "拍照", Toast.LENGTH_SHORT).show();
            pop.dismiss();
        }
    });
    pop.showAtLocation(pv, Gravity.BOTTOM, 0, 0);
}

private void show1(View v){
    View popView=View.inflate(this, R.layout.pop, null);
    final Button but_zan=(Button)popView.findViewById(R.id.but_zan);
    popView.measure(View.MeasureSpec.UNSPECIFIED, View.MeasureSpec.UNSPECIFIED);
    PopupWindow pop=new PopupWindow(popView,LayoutParams.WRAP_CONTENT,LayoutParams.WRAP_CONTENT);
    //点击空白处弹框消失
    pop.setOutsideTouchable(true);
    pop.setBackgroundDrawable(new ColorDrawable(0x00000000));
    
    //点击back键 弹框消失
    pop.setFocusable(true);
    
    //显示在左下方

// pop.showAsDropDown(v);

    //显示在左边
    int[] location=new int[2];
    //找到button在屏幕上的位置将宽高存入数组location中
    v.getLocationOnScreen(location);
    //获得popview位置
    int width=popView.getMeasuredWidth();
    //（设置popview的位置相对于父容器）将popview设置button的左边，宽度为button左上角位置坐标减去popview的宽度，高度为button的高度。
    but_zan.setOnClickListener(new OnClickListener() {
        
        @Override
        public void onClick(View v) {
            // TODO Auto-generated method stub
            String s=but_zan.getText().toString();
            if(s.equals("赞")){
                but_zan.setText("取消赞");
                img.setVisibility(View.VISIBLE);
            }else{
                but_zan.setText("赞");
                img.setVisibility(View.GONE);
            }
        }
    });
    pop.showAtLocation(v, Gravity.NO_GRAVITY, location[0]-width, location[1]);
}

}

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