Cannot cast from View to ProgressBar的解决办法

<span style="font-size:18px;">package mars.progressbar; import android.app.Activity; import android.content.DialogInterface.OnClickListener; import android.os.Bundle; import android.view.View; import android.widget.Button; public class ProgressBar extends Activity { /** Called when the activity is first created. */ //声明变量 private ProgressBar firstBar = null; private ProgressBar secondBar = null; private Button myButton = null; private int i = 0; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); //根据控件的ID来获取代表控件的对象 </span><span style="font-size:18px;"><span style="color:#ff6666;">firstBar = (ProgressBarTest)findViewById(R.id.firstBar); secondBar = (ProgressBarTest)findViewById(R.id.secondBar);</span> myButton = (Button)findViewById(R.id.myButton); myButton.setOnClickListener(new ButtonListener()); }</span>

红色部分一直提示Cannot cast from View to ProgressBar

 

原来是我命名类名跟调用的函数一样 起冲突了。

将ProgressBar类重新命名为ProgressBarTest  问题就解决了

 

public class ProgressBarTest extends Activity { /** Called when the activity is first created. */ //声明变量 private ProgressBar firstBar = null; private ProgressBar secondBar = null; private Button myButton = null; private int i = 0; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); //根据控件的ID来获取代表控件的对象 firstBar = (ProgressBar)findViewById(R.id.firstBar); secondBar = (ProgressBar)findViewById(R.id.secondBar); myButton = (Button)findViewById(R.id.myButton); myButton.setOnClickListener(new ButtonListener()); }

OK  这样就行了。