android PopupWindow的简单实用

public class MainActivity extends AppCompatActivity {

private RelativeLayout rl;

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
rl = (RelativeLayout) findViewById(R.id.rl_root);

}
public void showPopWindow(View v){
TextView tv = new TextView(this);
tv.setText("你好PopupWindow");
//创建popupwindow设置挂载的View控件,宽高,是否可以获得焦点
PopupWindow pop = new PopupWindow(tv,100,100,true);

//设置背景图片 如果需要透明背景ColorDrawable创建的时候不需要传参默认就是透明的

pop.setBackgroundDrawable(new ColorDrawable(Color.RED)); //现在在那个布局上,居中,xy偏移量 pop.showAtLocation(rl, Gravity.CENTER,0,0); }}

<Button
android:layout_width="wrap_content"
android:text="弹弹弹"
android:onClick="showPopWindow"
android:layout_height="wrap_content" />