可伸缩的textview详解(推荐)

public class MainActivity extends Activity {   private String str = "";    @Override  protected void onCreate(Bundle savedInstanceState) {     super.onCreate(savedInstanceState);     setContentView(R.layout.activity_main);      for (int i = 0; i < 200; i++) {       str = str + i + " ";     }     final ExpandableTextView etv = (ExpandableTextView) findViewById(R.id.etv);     etv.setText(str);      Button btn = (Button) findViewById(R.id.btn);      btn.setOnClickListener(new OnClickListener() {        @Override      public void onClick(View v) {         boolean b = etv.getExpandablestatus();          b = !b;         etv.setExpandable(b);        }     });    }  }