Question

我正在使用地图应用Android，并尝试在Google Maps v2 Android上使用AlphaSeekBar到我的多边形。我尝试使用SeekBar处理我的所有多边形，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

问题是你只保留一个多边形的引用如果要更新所有这些，则需要使用List mMutablePolygons;

然后创建每个多边形时：

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

mMutablePolygons.add(mPolygon);

并在更改搜索条值时：

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)));
        }
    }
}

在多边形谷歌地图v2 Android上使用AlphaBar

1 个答案: