首页 > 解决方案 > 如何从设置活动中获取字符串数据并将其发送到另一个活动?

问题描述

在我的设置活动中,用户可以更改他们的姓名。我想要做的是当用户更改他们的名字时,我想获取该数据并将另一个活动中的文本设置为新名称。

在我的设置活动中,我有这段代码:

if (preference instanceof EditTextPreference) {
    if (preference.getKey().equals("key_full_name")) {
        // update the changed name to summary filed
        preference.setSummary(stringValue);
        Intent returnIntent = new Intent();
        returnIntent.putExtra("new_Name", stringValue);
        setResult(Activity.RESULT_OK,returnIntent);
    }
}

stringValue具有存储新名称的数据。当用户单击设置屏幕左上角的后退按钮时,我想要它,另一个活动将文本设置为新名称。

这是显示文本的其他活动的 xml 文件:

<TextView
    android:id="@+id/myName"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="@string/default_full_name"
    android:textSize="35sp"
    android:textStyle="bold"
    app:layout_constraintBottom_toBottomOf="parent"
    app:layout_constraintEnd_toEndOf="parent"
    app:layout_constraintStart_toStartOf="parent"
    app:layout_constraintTop_toTopOf="parent"
    app:layout_constraintVertical_bias="0.358" />

编辑:包括 AppCompatPreferenceActivity.java 文件

package app.debata.com.debata;

import android.content.res.Configuration;
import android.os.Bundle;
import android.preference.PreferenceActivity;
import android.support.annotation.LayoutRes;
import android.support.annotation.Nullable;
import android.support.v7.app.ActionBar;
import android.support.v7.app.AppCompatDelegate;
import android.support.v7.widget.Toolbar;
import android.view.MenuInflater;
import android.view.View;
import android.view.ViewGroup;

/**
 * A {@link android.preference.PreferenceActivity} which implements and proxies the necessary calls
 * to be used with AppCompat.
 */
public abstract class AppCompatPreferenceActivity extends PreferenceActivity {

    private AppCompatDelegate mDelegate;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        getDelegate().installViewFactory();
        getDelegate().onCreate(savedInstanceState);
        super.onCreate(savedInstanceState);
    }

    @Override
    protected void onPostCreate(Bundle savedInstanceState) {
        super.onPostCreate(savedInstanceState);
        getDelegate().onPostCreate(savedInstanceState);
    }

    public ActionBar getSupportActionBar() {
        return getDelegate().getSupportActionBar();
    }

    public void setSupportActionBar(@Nullable Toolbar toolbar) {
        getDelegate().setSupportActionBar(toolbar);
    }

    @Override
    public MenuInflater getMenuInflater() {
        return getDelegate().getMenuInflater();
    }

    @Override
    public void setContentView(@LayoutRes int layoutResID) {
        getDelegate().setContentView(layoutResID);
    }

    @Override
    public void setContentView(View view) {
        getDelegate().setContentView(view);
    }

    @Override
    public void setContentView(View view, ViewGroup.LayoutParams params) {
        getDelegate().setContentView(view, params);
    }

    @Override
    public void addContentView(View view, ViewGroup.LayoutParams params) {
        getDelegate().addContentView(view, params);
    }

    @Override
    protected void onPostResume() {
        super.onPostResume();
        getDelegate().onPostResume();
    }

    @Override
    protected void onTitleChanged(CharSequence title, int color) {
        super.onTitleChanged(title, color);
        getDelegate().setTitle(title);
    }

    @Override
    public void onConfigurationChanged(Configuration newConfig) {
        super.onConfigurationChanged(newConfig);
        getDelegate().onConfigurationChanged(newConfig);
    }

    @Override
    protected void onStop() {
        super.onStop();
        getDelegate().onStop();
    }

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

    public void invalidateOptionsMenu() {
        getDelegate().invalidateOptionsMenu();
    }

    private AppCompatDelegate getDelegate() {
        if (mDelegate == null) {
            mDelegate = AppCompatDelegate.create(this, null);
        }
        return mDelegate;
    }
}

编辑:在 settings.java 文件中包含上述 if 语句的整个方法

private static Preference.OnPreferenceChangeListener sBindPreferenceSummaryToValueListener = new Preference.OnPreferenceChangeListener() {
        @Override
        public boolean onPreferenceChange(Preference preference, Object newValue) {
            String stringValue = newValue.toString();

            if (preference instanceof ListPreference) {
                // For list preferences, look up the correct display value in
                // the preference's 'entries' list.
                ListPreference listPreference = (ListPreference) preference;
                int index = listPreference.findIndexOfValue(stringValue);

                // Set the summary to reflect the new value.
                preference.setSummary(
                        index >= 0
                                ? listPreference.getEntries()[index]
                                : null);

            } else if (preference instanceof RingtonePreference) {
                // For ringtone preferences, look up the correct display value
                // using RingtoneManager.
                if (TextUtils.isEmpty(stringValue)) {
                    // Empty values correspond to 'silent' (no ringtone).
                    preference.setSummary(R.string.pref_ringtone_silent);

                } else {
                    Ringtone ringtone = RingtoneManager.getRingtone(
                            preference.getContext(), Uri.parse(stringValue));

                    if (ringtone == null) {
                        // Clear the summary if there was a lookup error.
                        preference.setSummary(R.string.default_ringtone);
                    } else {
                        // Set the summary to reflect the new ringtone display
                        // name.
                        String name = ringtone.getTitle(preference.getContext());
                        preference.setSummary(name);
                    }
                }

            } else if (preference instanceof EditTextPreference) {
                if (preference.getKey().equals("key_full_name")) {
                    // update the changed name to summary filed
                    preference.setSummary(stringValue);
                    Intent returnIntent = new Intent();
                    returnIntent.putExtra("new_Name", stringValue);
                    setResult(Activity.RESULT_OK,returnIntent);
                } else if (preference.getKey().equals("key_username")) {
                    // update the changed gallery name to summary filed
                    preference.setSummary(stringValue);
                } else if (preference.getKey().equals("key_birthday")) {
                    // update the changed gallery name to summary filed
                    preference.setSummary(stringValue);
                } else if (preference.getKey().equals("key_email")) {
                    // update the changed gallery name to summary filed
                    preference.setSummary(stringValue);
                }
            } else {
                preference.setSummary(stringValue);
            }
            return true;
        }
    };

标签: javaandroidxmlandroid-studiosettings

解决方案


如果您将值存储在共享首选项中,您可以OnSharedPreferencesChangedListener在需要获取新数据的活动中使用。https://developer.android.com/reference/android/content/SharedPreferences.OnSharedPreferenceChangeListeneronResumeonCreate. _

另一种选择是保存到数据库。然后您可以使用返回 LiveData 对象的 Room 库。如果数据发生更改,LiveData 将自动更新屏幕。


推荐阅读