在多边形Google地图v2上使用AlphaBar Android

Question

我正在使用地图应用程序Android，并尝试在Google Maps v2 Android上使用AlphaSeekBar指定我的多边形。 我尝试使用我的所有多边形上的SeekBar，但事实证明只是在最后一个多边形上工作。

这是我的代码：

private static final int ALPHA_MAX = 255; 
    private SeekBar mAlphaBar; 
    private Polygon mMutablePolygon; 
    private GoogleMap mMap; 

    ......................................... 

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

     mAlphaBar = (SeekBar) findViewById(R.id.alphaSeekBar); 
     mAlphaBar.setMax(ALPHA_MAX); 
     mAlphaBar.setProgress(127); 

     mMessageView = (TextView) findViewById(R.id.message_text); 
     setUpMapIfNeeded(); 
    } 

    @Override 
    protected void onResume() { 
     super.onResume(); 
     setUpMapIfNeeded(); 
    } 

private void setUpMapIfNeeded() { 
     // Do a null check to confirm that we have not already instantiated the map. 
     if (mMap == null) { 
      // Try to obtain the map from the SupportMapFragment. 
      mMap = ((SupportMapFragment) getSupportFragmentManager().findFragmentById(R.id.map)) 
        .getMap(); 
      // Check if we were successful in obtaining the map. 
      if (mMap != null) { 

       mMap.setMyLocationEnabled(true); 
       mMap.setPadding(currentLeft, currentTop, currentRight, currentBottom); 
       mMap.moveCamera(CameraUpdateFactory.newLatLngZoom(DR, 14)); 

       // poligon area -- 
       { 
       PolygonOptions options = new PolygonOptions() 
       .add(dr_1,dr_2,dr_3,dr_4,dr_5,dr_6,dr_7,dr_8,dr_9,dr_10,dr_11,dr_12,dr_13,dr_14,dr_15,dr_16,dr_17) ; 
       mMutablePolygon = mMap.addPolygon(options 
         .strokeColor(Color.RED) 
         .strokeWidth(1) 
         .fillColor(Color.CYAN)); 

PolygonOptions gt =new PolygonOptions() 
       .add(gt_1,gt_2,gt_3,gt_4,gt_5,gt_6,gt_7,gt_8,gt_9,gt_10,gt_11,gt_12,gt_13,gt_14,gt_15,gt_16) ; 
       mMutablePolygon = mMap.addPolygon(gt 
         .strokeColor(Color.RED) 
         .strokeWidth(1) 
         .fillColor(Color.GREEN)); 
       mAlphaBar.setOnSeekBarChangeListener(this); 
} 

// Add a camera change listener. 
       mMap.setOnCameraChangeListener(new OnCameraChangeListener() { 
        public void onCameraChange(CameraPosition pos) { 
         mMessageView.setText("CameraChangeListener: " + pos); 
        } 
        }); 
      } 
     } 
    } 

public void onStopTrackingTouch(SeekBar seekBar) { 
     // Don't do anything here. 
    } 


    public void onStartTrackingTouch(SeekBar seekBar) { 
     // Don't do anything here. 
    } 


    public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) { 
     if (mMutablePolygon == null) { 
      return; 
     } 

     if (seekBar == mAlphaBar) { 
      int prevColor = mMutablePolygon.getFillColor(); 
      mMutablePolygon.setFillColor(Color.argb(
        progress, Color.red(prevColor), Color.green(prevColor), 
        Color.blue(prevColor))); 
     } 
    } 
} 

Answer 1

的问题是，你只用1个参考多边形 如果要更新所有的人，你需要使用一个列表mMutablePolygons;

然后在创建每个多边形：

mPolygon = mMap.addPolygon(options 
        .strokeColor(Color.RED) 
        .strokeWidth(1) 
        .fillColor(Color.CYAN)); 

mMutablePolygons.add(mPolygon); 

，并改变搜索条价值时：

public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) { 
    if (mMutablePolygons == null || mMutablePolygons.isEmpty()) { 
     return; 
    } 

    if (seekBar == mAlphaBar) { 
     for(Polygon mpoly : mMutablePolygons){ 
      int prevColor = mpoly.getFillColor(); 
      mpoly.setFillColor(Color.argb(progress, Color.red(prevColor), Color.green(prevColor),Color.blue(prevColor))); 
     } 
    } 
}