com.esri.arcgisruntime.sample.stretchrenderer.MainActivity.java Source code

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Here is the source code for com.esri.arcgisruntime.sample.stretchrenderer.MainActivity.java

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/* Copyright 2017 Esri
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 */

package com.esri.arcgisruntime.sample.stretchrenderer;

import java.io.File;
import java.util.Collections;

import android.Manifest;
import android.content.pm.PackageManager;
import android.os.Bundle;
import android.os.Environment;
import android.support.annotation.NonNull;
import android.support.v4.app.ActivityCompat;
import android.support.v4.app.FragmentManager;
import android.support.v4.content.ContextCompat;
import android.support.v7.app.AppCompatActivity;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.widget.Toast;

import com.esri.arcgisruntime.layers.RasterLayer;
import com.esri.arcgisruntime.mapping.ArcGISMap;
import com.esri.arcgisruntime.mapping.Basemap;
import com.esri.arcgisruntime.mapping.view.MapView;
import com.esri.arcgisruntime.raster.MinMaxStretchParameters;
import com.esri.arcgisruntime.raster.PercentClipStretchParameters;
import com.esri.arcgisruntime.raster.Raster;
import com.esri.arcgisruntime.raster.StandardDeviationStretchParameters;
import com.esri.arcgisruntime.raster.StretchParameters;
import com.esri.arcgisruntime.raster.StretchRenderer;

public class MainActivity extends AppCompatActivity implements ParametersDialogFragment.ParametersListener {

    private FragmentManager mFragmentManager;

    private MapView mMapView;
    private RasterLayer mRasterLayer;

    private int mMin;
    private int mMax;
    private int mPercentClipMin;
    private int mPercentClipMax;
    private int mStdDevFactor;
    private StretchType mStretchType;

    @Override
    public void returnParameters(int min, int max, int percentClipMin, int percentClipMax, int stdDevFactor,
            StretchType stretchType) {
        //gets dialog box parameters and calls updateRenderer
        mMin = min;
        mMax = max;
        mPercentClipMin = percentClipMin;
        mPercentClipMax = percentClipMax;
        mStdDevFactor = stdDevFactor;
        mStretchType = stretchType;
        updateRenderer();
    }

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        //set default values for stretch parameters
        mMin = 0;
        mMax = 255;
        mPercentClipMin = 0;
        mPercentClipMax = 99;
        mStdDevFactor = 1;
        mStretchType = StretchType.MIN_MAX;
        // retrieve the MapView from layout
        mMapView = (MapView) findViewById(R.id.mapView);
        mFragmentManager = getSupportFragmentManager();
        // define permission to request
        String[] reqPermission = new String[] { Manifest.permission.WRITE_EXTERNAL_STORAGE };
        int requestCode = 2;
        // For API level 23+ request permission at runtime
        if (ContextCompat.checkSelfPermission(MainActivity.this,
                reqPermission[0]) == PackageManager.PERMISSION_GRANTED) {
            initialize();
        } else {
            // request permission
            ActivityCompat.requestPermissions(MainActivity.this, reqPermission, requestCode);
        }
    }

    /**
     * Using values stored in strings.xml, builds path to raster.
     *
     * @return the path to raster file
     */
    private String buildRasterPath(String filename) {
        // get sdcard resource name
        File extStorDir = Environment.getExternalStorageDirectory();
        // get the directory
        String extSDCardDirName = this.getResources().getString(R.string.raster_folder);
        // create the full path to the raster file
        return extStorDir.getAbsolutePath() + File.separator + extSDCardDirName + File.separator + filename
                + ".tif";
    }

    /**
     * Creates new imagery raster based on a given path, creates an ArcGISMap, sets it to a MapView and
     * calls updateRenderer().
     */
    private void initialize() {
        // create raster
        Raster raster = new Raster(
                new File(buildRasterPath(this.getString(R.string.shasta_file))).getAbsolutePath());
        mRasterLayer = new RasterLayer(raster);
        // create a basemap from the raster layer
        Basemap basemap = new Basemap(mRasterLayer);
        ArcGISMap map = new ArcGISMap(basemap);
        // add the map to a map view
        mMapView.setMap(map);
        updateRenderer();
    }

    /**
     * Creates StretchRenderer of the chosen type: MinMax, PercentClip or StandardDeviation.
     */
    private void updateRenderer() {
        StretchParameters stretchParameters;
        switch (mStretchType) {
        default:
            stretchParameters = new MinMaxStretchParameters(Collections.singletonList((double) mMin),
                    Collections.singletonList((double) mMax));
            break;
        case PERCENT_CLIP:
            stretchParameters = new PercentClipStretchParameters(mPercentClipMin, mPercentClipMax);
            break;
        case STANDARD_DEVIATION:
            stretchParameters = new StandardDeviationStretchParameters(mStdDevFactor);
        }
        StretchRenderer stretchRenderer = new StretchRenderer(stretchParameters, null, true, null);
        mRasterLayer.setRasterRenderer(stretchRenderer);
    }

    /**
     * Handle the permissions request response.
     */
    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions,
            @NonNull int[] grantResults) {
        if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
            initialize();
        } else {
            // report to user that permission was denied
            Toast.makeText(MainActivity.this,
                    getResources().getString(R.string.stretch_renderer_write_permission_denied), Toast.LENGTH_SHORT)
                    .show();
        }
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        MenuInflater inflater = getMenuInflater();
        inflater.inflate(R.menu.blend_parameters, menu);
        return super.onCreateOptionsMenu(menu);
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        //send parameters to fragment
        ParametersDialogFragment paramDialog = new ParametersDialogFragment();
        Bundle stretchParameters = new Bundle();
        stretchParameters.putInt("min", mMin);
        stretchParameters.putInt("max", mMax);
        stretchParameters.putInt("percent_clip_min", mPercentClipMin);
        stretchParameters.putInt("percent_clip_max", mPercentClipMax);
        stretchParameters.putInt("std_dev_factor", mStdDevFactor);
        stretchParameters.putSerializable("stretch_type", mStretchType);
        paramDialog.setArguments(stretchParameters);
        paramDialog.show(mFragmentManager, "param_dialog");
        return super.onOptionsItemSelected(item);
    }

    @Override
    protected void onPause() {
        super.onPause();
        mMapView.pause();
    }

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

    @Override
    protected void onDestroy() {
        super.onDestroy();
        mMapView.dispose();
    }

    enum StretchType {
        MIN_MAX("Min Max"), PERCENT_CLIP("Percent Clip"), STANDARD_DEVIATION("Standard Deviation");

        private final String stringValue;

        StretchType(String toString) {
            stringValue = toString;
        }

        @Override
        public String toString() {
            return stringValue;
        }
    }
}