如何更改gridview中的項目顏色在android

Question

上午在做一個應用程序在這裏顯示A到Z值在gridview中使用textview，之後，當我點擊字母表去了一些其他activity..up到我做了，我的問題是如果我點擊「A」字母表，然後我必須去Activity2然後我回到以前的活動（GridViewAcvtivity）意味着現在我需要只顯示紅色的「A」字母文本，保持默認顏色的所有字母，然後再次我點擊「B」字母表，然後我會去其他一些Activity2然後我回到GridviewActivity意味着時間只有「A和B」字母應該在「紅色」字母仍然是所有默認顏色..我嘗試使用下面的代碼，一旦我點擊一個字母表，他們要去Activity2，然後回到GridviewActivity那個時候所有的字母都是紅色的，但我只想顯示紅色的字母，任何一個給我一些想法。

public class GridViewActivity extends Activity { 

GridView gridView; 

static final String[] MOBILE_OS = new String[] { "A", "B", 
     "C", "D","E","F","G","H","I","J","K","L","M","N","O","P","Q","R","S","T","U","V","W","X","Y","Z"}; 

@Override 
public void onCreate(Bundle savedInstanceState) { 

    super.onCreate(savedInstanceState); 
    setContentView(R.layout.main); 

    gridView = (GridView) findViewById(R.id.gridView1); 

    gridView.setAdapter(new ImageAdapter(this, MOBILE_OS)); 

    gridView.setOnItemClickListener(new OnItemClickListener() { 
     public void onItemClick(AdapterView<?> parent, View v, 
       int position, long id) { 
     Toast.makeText(
        getApplicationContext(),""+position, Toast.LENGTH_SHORT).show(); 
      GlobalClass.value1=1; 
      Intent i=new Intent(GridViewActivity.this,Activity2.class); 
      i.putExtra("k1", "position"); 
      startActivity(i); 
      } 
    }); 

} 
public class ImageAdapter extends BaseAdapter { 
    private Context context; 
    private final String[] mobileValues; 

    public ImageAdapter(Context context, String[] mobileValues) { 
     this.context = context; 
     this.mobileValues = mobileValues; 
    } 

    public View getView(int position, View convertView, ViewGroup parent) { 

     LayoutInflater inflater = (LayoutInflater) context 
       .getSystemService(Context.LAYOUT_INFLATER_SERVICE); 

     View gridView; 

     if (convertView == null) { 

      gridView = new View(context); 

      // get layout from mobile.xml 
      gridView = inflater.inflate(R.layout.mobile, null); 

      // set value into textview 
      TextView textView = (TextView) gridView 
        .findViewById(R.id.grid_item_label); 
      textView.setText(mobileValues[position]); 

      if(GlobalClass.value1==1) 
      { 
       textView.setTextColor(Color.RED); 
      } 
      } else { 
      gridView = (View) convertView; 
     } 

     return gridView; 
    } 

    @Override 
    public int getCount() { 
     return mobileValues.length; 
    } 

    @Override 
    public Object getItem(int position) { 
     return null; 
    } 

    @Override 
    public long getItemId(int position) { 
     return 0; 
    } 

} 


String mLabelsIds[]={"RED","YELLOW","black"}; 
     } 

Answer 1

在setOnItemClickListener()開始活動之前改變當前點擊字母的顏色。當你回來時，文本應該已經預先着色。

事情是這樣的：

gridView.setOnItemClickListener(new OnItemClickListener() { 
    public void onItemClick(AdapterView<?> parent, View v, int position, long id) { 
     TextView currentLetter = (TextView) v.findViewById(R.id.grid_item_label); 
     currentLetter.setTextColor(Color.GREEN); 

     // start Activity2 here 
    } 
} 

作爲一個側面說明，提供了getItem()和getItemId()方法的實現，否則你可能會得到奇怪的行爲。

@Override 
public Object getItem(int position) { 
    return mobileValues[position]; //return the element from array at specified position 
} 

@Override 
public long getItemId(int position) { 
    return position; //usually the item id is its position. 
}