单例中使用Context内存泄漏问题

简介: 在单例中但凡声明Context context，开发工具都会提示Do not place Android context classes in static fields (static reference to Single which has field mContext pointing to Context); this is a memory leak (and also breaks Instant Run) 意思是说可能存在内存泄漏。因为在单例中使用的静态类，是伴随着app的生命周期的，所以在此处使用Context context 会导致context无法被顺利回收。

一、原始代码

public class Single {
    private Context mContext;
    private static Single instance = null; //此处提示内存泄漏
    public static synchronized Single getInstance() {
        synchronized (Single.class) {
            if (instance == null) {
                instance = new Single();
        return instance;
    public void init(Context context) {
        mContext = context;
    public void getScreenWidth() {
        ScreenUtils.getScreenWidth(mContext);
二、解决办法
将context换成context.getApplicationContext()，此时还会提示有内存泄漏，很多开发者反馈是androidStudio的bug，如果不想有这个提示，需要忽略警告，对变量添加@SuppressLint("StaticFieldLeak")
完整代码如下
public class Single {
    private Context mContext;
    @SuppressLint("StaticFieldLeak") //忽略警告
    private static Single instance = null; //此处提示内存泄漏
    public static synchronized Single getInstance() {
        synchronized (Single.class) {
            if (instance == null) {
                instance = new Single();
        return instance;
    public void init(Context context) {
        mContext = context.getApplicationContext();//将`context`换成`context.getApplicationContext()`
    public void getScreenWidth() {
        ScreenUtils.getScreenWidth(mContext);
不临时保存Context，在需要使用场景下，直接传入该方法。
public class Single {
    private static Single instance = null; //此处提示内存泄漏
    public static synchronized Single getInstance() {
        synchronized (Single.class) {
            if (instance == null) {
                instance = new Single();
        return instance;
    public void getScreenWidth(Context context) { //直接引用传入的context
        ScreenUtils.getScreenWidth(context);
我自己使用的是第二种方法，并且加上了
context.getApplicationContext()
当然，你需要了解，context与applicationContext的区别，以及你项目中场景如何应用。
三、参考链接
stackoverflow.com/questions/3…
stackoverflow.com/questions/3…