CustomDefaultPreference.java

package org.thoughtcrime.SMP.components;

import android.app.AlertDialog;
import android.content.Context;
import android.content.res.TypedArray;
import android.os.Bundle;
import android.preference.DialogPreference;
import android.support.annotation.NonNull;
import android.text.Editable;
import android.text.TextUtils;
import android.text.TextWatcher;
import android.util.AttributeSet;
import android.view.View;
import android.widget.AdapterView;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Spinner;
import android.widget.TextView;

import org.thoughtcrime.SMP.R;
import org.thoughtcrime.SMP.util.TextSecurePreferences;

import java.net.URI;
import java.net.URISyntaxException;


public class CustomDefaultPreference extends DialogPreference {

  private static final String TAG = CustomDefaultPreference.class.getSimpleName();

  private final int    inputType;
  private final String customPreference;
  private final String customToggle;

  private CustomPreferenceValidator validator;
  private String                    defaultValue;

  private Spinner  spinner;
  private EditText customText;
  private TextView defaultLabel;
  private Button   positiveButton;

  public CustomDefaultPreference(Context context, AttributeSet attrs) {
    super(context, attrs);

    int[]      attributeNames = new int[]{android.R.attr.inputType, R.attr.custom_pref_toggle};
    TypedArray attributes     = context.obtainStyledAttributes(attrs, attributeNames);

    this.inputType        = attributes.getInt(0, 0);
    this.customPreference = getKey();
    this.customToggle     = attributes.getString(1);
    this.validator        = new NullValidator();

    attributes.recycle();

    setPersistent(false);
    setDialogLayoutResource(R.layout.custom_default_preference_dialog);
  }

  public CustomDefaultPreference setValidator(CustomPreferenceValidator validator) {
    this.validator = validator;
    return this;
  }

  public CustomDefaultPreference setDefaultValue(String defaultValue) {
    this.defaultValue = defaultValue;
    this.setSummary(getSummary());
    return this;
  }

  @Override
  public String getSummary() {
    if (isCustom()) {
      return getContext().getString(R.string.CustomDefaultPreference_using_custom,
                                    getPrettyPrintValue(getCustomValue()));
    } else {
      return getContext().getString(R.string.CustomDefaultPreference_using_default,
                                    getPrettyPrintValue(getDefaultValue()));
    }
  }

  @Override
  protected void onBindDialogView(@NonNull View view) {
    super.onBindDialogView(view);

    this.spinner      = (Spinner) view.findViewById(R.id.default_or_custom);
    this.defaultLabel = (TextView) view.findViewById(R.id.default_label);
    this.customText   = (EditText) view.findViewById(R.id.custom_edit);

    this.customText.setInputType(inputType);
    this.customText.addTextChangedListener(new TextValidator());
    this.customText.setText(getCustomValue());
    this.spinner.setOnItemSelectedListener(new SelectionLister());
    this.defaultLabel.setText(getPrettyPrintValue(defaultValue));
  }

  @Override
  protected void showDialog(Bundle instanceState) {
    super.showDialog(instanceState);
    positiveButton = ((AlertDialog)getDialog()).getButton(AlertDialog.BUTTON_POSITIVE);

    if (isCustom()) spinner.setSelection(1, true);
    else            spinner.setSelection(0, true);
  }

  @Override
  protected void onDialogClosed(boolean positiveResult) {
    if (positiveResult) {
      if (spinner != null)    setCustom(spinner.getSelectedItemPosition() == 1);
      if (customText != null) setCustomValue(customText.getText().toString());

      setSummary(getSummary());
    }
  }

  private String getPrettyPrintValue(String value) {
    if (TextUtils.isEmpty(value)) return getContext().getString(R.string.CustomDefaultPreference_none);
    else                          return value;
  }

  private boolean isCustom() {
    return TextSecurePreferences.getBooleanPreference(getContext(), customToggle, false);
  }

  private void setCustom(boolean custom) {
    TextSecurePreferences.setBooleanPreference(getContext(), customToggle, custom);
  }

  private String getCustomValue() {
    return TextSecurePreferences.getStringPreference(getContext(), customPreference, "");
  }

  private void setCustomValue(String value) {
    TextSecurePreferences.setStringPreference(getContext(), customPreference, value);
  }

  private String getDefaultValue() {
    return defaultValue;
  }

  private class SelectionLister implements AdapterView.OnItemSelectedListener {

    @Override
    public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
      defaultLabel.setVisibility(position == 0 ? View.VISIBLE : View.GONE);
      customText.setVisibility(position == 0 ? View.GONE : View.VISIBLE);
      positiveButton.setEnabled(position == 0 || validator.isValid(customText.getText().toString()));
    }

    @Override
    public void onNothingSelected(AdapterView<?> parent) {
      defaultLabel.setVisibility(View.VISIBLE);
      customText.setVisibility(View.GONE);
    }
  }

  private class TextValidator implements TextWatcher {

    @Override
    public void beforeTextChanged(CharSequence s, int start, int count, int after) {}

    @Override
    public void onTextChanged(CharSequence s, int start, int before, int count) {}

    @Override
    public void afterTextChanged(Editable s) {
      if (spinner.getSelectedItemPosition() == 1) {
        positiveButton.setEnabled(validator.isValid(s.toString()));
      }
    }
  }

  protected interface CustomPreferenceValidator {
    public boolean isValid(String value);
  }

  private static class NullValidator implements CustomPreferenceValidator {
    @Override
    public boolean isValid(String value) {
      return true;
    }
  }

  public static class UriValidator implements CustomPreferenceValidator {
    @Override
    public boolean isValid(String value) {
      if (TextUtils.isEmpty(value)) return true;

      try {
        new URI(value);
        return true;
      } catch (URISyntaxException mue) {
        return false;
      }
    }
  }

  public static class HostnameValidator implements CustomPreferenceValidator {
    @Override
    public boolean isValid(String value) {
      if (TextUtils.isEmpty(value)) return true;

      try {
        URI uri = new URI(null, value, null, null);
        return true;
      } catch (URISyntaxException mue) {
        return false;
      }
    }
  }

  public static class PortValidator implements CustomPreferenceValidator {
    @Override
    public boolean isValid(String value) {
      try {
        Integer.parseInt(value);
        return true;
      } catch (NumberFormatException e) {
        return false;
      }
    }
  }



}