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;//在代码中可以随意设置listview的宽度       }}