android动态设置listview的宽

public class AllFileBrowser extends Activity {

      private int ScreenWIDTH;

      private  ListView listViewFile;

     protected void onCreate(Bundle savedInstanceState) {

            //获取屏幕像素宽度

           DisplayMetrics dMetrics = new DisplayMetrics();
           getWindowManager().getDefaultDisplay().getMetrics(dMetrics);
           ScreenWIDTH = dMetrics.widthPixels;

            listViewFile = (ListView) findViewById(R.id.listView);

     }

    @Override
     public void onWindowFocusChanged(boolean hasFocus) {
           super.onWindowFocusChanged(hasFocus);
          listViewFile .getLayoutParams().width=ScreenWIDTH*6/9;//在代码中能够随意设置listview的宽度
      }}