如何動態更新TextView文本

在BroadcastReceiver內部我跟蹤每次下載列表時每次都是我想用上次更新textview。我做了以下，但時間永遠不會顯示。如何動態更新TextView文本

@Override 
public void onReceive(Context context, Intent intent) { 
_context = context; 
Toast.makeText(context, "ListDownloadReceiver....", Toast.LENGTH_SHORT) 
    .show(); 

boolean force = intent.getBooleanExtra("FORCE", false); 

long nextUpdateTime = getUpdateTime(); 

if (force || nextUpdateTime < System.currentTimeMillis()) { 
    if (isNetworkAvailable()) { 
    Log.i(LIST_DOWNLOAD_RECEIVER, 
     "Going to be downloading the list..."); 
    DownloadListData downloadList = new DownloadListData(context); 
    downloadList.execute(); 

    } else { 
    Log.i(LIST_DOWNLOAD_RECEIVER, "Not connected..."); 
    context.registerReceiver(this, new IntentFilter(
     ConnectivityManager.CONNECTIVITY_ACTION)); 
    } 
} 

DatabaseHandler db = DatabaseHandler.getInstance(context); 
String timeFormat = "d/M/yyyy 'at' k:mm:ss"; 

long lastUpdate = Long.valueOf(db.getPreference("LAST_UPDATED_TIME", 
    "0")); 

CharSequence time = DateFormat.format(timeFormat, lastUpdate); 
Log.i(LIST_DOWNLOAD_RECEIVER, "Time is: " + time); 

LayoutInflater inflater = (LayoutInflater) context 
    .getSystemService(Context.LAYOUT_INFLATER_SERVICE); 
View view = inflater.inflate(R.layout.activity_main, null); 
TextView tv = (TextView) view.findViewById(R.id.lastRefreshed); 
tv.append("Blah: " + time); 

}

這是我的.xml文件

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" 
    xmlns:tools="http://schemas.android.com/tools" 
    android:layout_width="fill_parent" 
    android:layout_height="fill_parent" 
    android:gravity="left|top" 
    android:orientation="vertical" > 

    <LinearLayout 
     xmlns:android="http://schemas.android.com/apk/res/android" 
     android:id="@+id/noShowsLayout" 
     android:layout_width="match_parent" 
     android:layout_height="115dp" 
     android:orientation="horizontal" 
     android:background="@color/blue" > 

     <TextView 
      android:id="@+id/noShowsTextView" 
      android:layout_width="match_parent" 
      android:layout_height="fill_parent" 
      android:gravity="center" 
      android:text="@string/no_added_shows" 
      android:textAppearance="?android:attr/textAppearanceMedium" 
      android:textSize="18dip" /> 
    </LinearLayout> 

    <LinearLayout 
     xmlns:android="http://schemas.android.com/apk/res/android" 
     android:layout_width="fill_parent" 
     android:layout_height="0dp" 
     android:layout_weight="1" 
     android:orientation="horizontal" > 

     <ListView 
      android:id="@+id/listView1" 
      android:layout_width="fill_parent" 
      android:layout_height="wrap_content" > 
     </ListView> 
    </LinearLayout> 

    <LinearLayout 
     xmlns:android="http://schemas.android.com/apk/res/android" 
     android:layout_width="fill_parent" 
     android:layout_height="48dp" 
     android:layout_gravity="bottom" 
     android:background="@color/blue" 
     android:orientation="horizontal" > 

     <ImageButton 
      android:id="@+id/refreshButton" 
      android:layout_width="wrap_content" 
      android:layout_height="wrap_content" 
      android:layout_gravity="left" 
      android:contentDescription="@string/refresh" 
      android:src="@drawable/refresh"/> 

     <TextView 
      android:id="@+id/lastRefreshed" 
      android:layout_width="0dp" 
      android:layout_height="wrap_content" 
      android:layout_weight="1" 
      android:layout_gravity="center" 
      android:layout_marginLeft="5dp" 
      android:text="@string/lastRefreshTime" 
      android:textAppearance="?android:attr/textAppearanceSmall" /> 

     <ImageButton 
      android:id="@+id/button1" 
      android:layout_width="wrap_content" 
      android:layout_height="wrap_content" 
      android:layout_gravity="right" 
      android:contentDescription="@string/remove_tv_show" 
      android:src="@drawable/content_discard" 
      android:clickable="false"/> 


    </LinearLayout> 

</LinearLayout>

來源

2012-10-31 da3m0n

你已經寫了下面一行顯示在TextView的文本，

TextView tv = (TextView) view.findViewById(R.id.lastRefreshed); 
tv.append("Blah: " + time);

我建議你使用.setText（）方法，而不是.append（）方法如下，

TextView tv = (TextView) view.findViewById(R.id.lastRefreshed); 
tv.setText("Blah: " + time); 
view.invalidate(); // for refreshment

來源

2012-10-31 01:51:57 Lucifer

對不起，應該提到，我已經嘗試過，並沒有喜悅。 – da3m0n

哦，我還沒有看到，你是動態添加視圖，讓我更新我的答案，現在檢查它，你需要調用.invalidate（）方法刷新 – Lucifer

添加了xml，希望正確:) – da3m0n

在run（）方法內部創建一個新線程，編寫代碼以更新所考慮的字段，然後啓動循環。請務必記住，您必須在UI線程上執行更新操作。

來源

2016-10-11 10:03:57

如何動態更新TextView文本

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