创建进度条

Question

我已经创建了一个android程序。现在我想要一个带有我的应用程序名称的屏幕和一个加载符号启动的进度条。进度条应该等待3秒钟，然后我的程序必须加载。如何才能执行这个？

Answer 1

你想实施的事情被称为Splashscreen。对于这一点：

创建活动SplashScreenActivity.java：

public class SplashScreenActivity extends Activity { 

ProgressDialog mProgressDialog; 

@Override 
protected void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.activity_splash_screen); 

    mProgressDialog = ProgressDialog.show(this, 
        "Loading", "Please wait...", true); 

    new Handler().postDelayed(new Runnable() { 
     @Override 
     public void run() { 

      mProgressDialog.dismiss(); 
      startActivity(new Intent(SplashScreenActivity.this, SecondActivity.class)); 
      finish(); 
     } 
    }, 3000); 
} 
} 

，然后创建另一个活动SecondActivity.java。将您的SplashScreenActivity.java设为启动程序活动，然后运行您的项目。

编辑：

为了使您的活动作为一个启动活动，只需添加以下线路中的相关活动标签：

<intent-filter> 
      <action android:name="android.intent.action.MAIN" /> 

      <category android:name="android.intent.category.LAUNCHER" /> 
</intent-filter> 

Answer 2

pgbar.xml：

<?xml version="1.0" encoding="utf-8"?> 
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" 
android:layout_width="match_parent" 
android:layout_height="match_parent" 
android:orientation="vertical" > 

<ProgressBar 
    android:id="@+id/progressBar1" 
    style="?android:attr/progressBarStyleLarge" 
    android:layout_width="wrap_content" 
    android:layout_height="wrap_content" /> 

</LinearLayout> 

pgbar.java

public class SplashScreen extends Activity { 

private static int SPLASH_TIME_OUT = 3000; 
ProgressBar mProgress; 
@Override 
protected void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.pgbar); 

    mProgress = (ProgressBar) findViewById(R.id.progressBar1); 
    mProgress .setCancelable(true); 
    mProgress .setMessage("Loading Please wait ..."); 
    mProgress .setProgress(0); 
    mProgress .setMax(100); 
    mProgress .show(); 


    new Handler().postDelayed(new Runnable() { 

     @Override 
     public void run() { 
      Intent i = new Intent(pgbar.this, NextActivity.class); 
      startActivity(i); 
      finish(); 
     } 
    }, SPLASH_TIME_OUT); 
} 

}