TextSizeEnterSharedElementCallback.java

package com.hannesdorfmann.mosby3.sample.mail.ui.transition;

import android.annotation.TargetApi;
import android.app.SharedElementCallback;
import android.content.Context;
import android.content.res.Resources;
import android.util.TypedValue;
import android.view.View;
import android.widget.TextView;
import com.hannesdorfmann.mosby3.sample.mail.R;
import java.util.List;

@TargetApi(21)
public class TextSizeEnterSharedElementCallback extends SharedElementCallback {
  private static final String TAG = "EnterSharedElementCallback";

  private final float mStartTextSize;
  private final float mEndTextSize;

  public TextSizeEnterSharedElementCallback(Context context) {
    Resources res = context.getResources();
    mStartTextSize = res.getDimensionPixelSize(R.dimen.list_mail_item_subject_text_size);
    mEndTextSize = res.getDimensionPixelSize(R.dimen.details_subject_text_size);
  }

  @Override
  public void onSharedElementStart(List<String> sharedElementNames, List<View> sharedElements,
      List<View> sharedElementSnapshots) {

    TextView textView = findTextView(sharedElements);

    // Setup the TextView's start values.
    textView.setTextSize(TypedValue.COMPLEX_UNIT_PX, mStartTextSize);
  }

  @TargetApi(21) private TextView findTextView(List<View> sharedElements) {
    for (View v : sharedElements) {
      if (v.getTransitionName().equals(v.getResources().getString(R.string.shared_mail_subject))) {
        return (TextView) v;
      }
    }
    return null;
  }

  @Override
  public void onSharedElementEnd(List<String> sharedElementNames, List<View> sharedElements,
      List<View> sharedElementSnapshots) {

    TextView textView = findTextView(sharedElements);

    // Setup the TextView's end values.
    textView.setTextSize(TypedValue.COMPLEX_UNIT_PX, mEndTextSize);

  }
}