ProgressBar用于在界面上显示一个进度条，表示我们的程序正在加载一些数据。

 

 

package com.example.uiwidgettest2; import android.app.Activity; import android.os.Bundle; import android.view.View; import android.widget.*; public class edittextActivity extends Activity{
      private ProgressBar progressBar = null;     private Button btn1 = null;     private Button btn2 = null;     @Override     protected void onCreate(Bundle savedInstanceState) {
          super.onCreate(savedInstanceState);         setContentView(R.layout.edittext);         progressBar = (ProgressBar)findViewById(R.id.progress_bar);         btn1 = (Button)findViewById(R.id.button1);         btn2 = (Button)findViewById(R.id.button2);         btn1.setOnClickListener(new View.OnClickListener() {
              @Override             public void onClick(View v) {
                  if(progressBar.getVisibility() == View.VISIBLE){
                      progressBar.setVisibility(View.GONE);                 }             }         });         btn2.setOnClickListener(new View.OnClickListener() {
              @Override             public void onClick(View v) {
                  if(progressBar.getVisibility() == View.GONE){
                      progressBar.setVisibility(v.VISIBLE);                 }             }         });     } }

 

 

 

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package com.example.uiwidgettest2; import android.app.Activity; import android.os.Bundle; import android.view.View; import android.widget.*; public class edittextActivity extends Activity{
      private ProgressBar progressBar = null;     private Button btn1 = null;     @Override     protected void onCreate(Bundle savedInstanceState) {
          super.onCreate(savedInstanceState);         setContentView(R.layout.edittext);         progressBar = (ProgressBar)findViewById(R.id.progress_bar);         btn1 = (Button)findViewById(R.id.button1);         btn1.setOnClickListener(new View.OnClickListener() {
              @Override             public void onClick(View v) {
                  int progress = progressBar.getProgress();                 progress = progress+10;                 if(progressBar.getProgress() <= 100){
                      progressBar.setProgress(progress);                 }             }         });     } }