逐行解析代码，不要修改和遗漏源代码，去除行号：
1905 /**
1906 * Returns a list of the names of available location providers. If {@code enabledOnly} is false,
1907 * this is functionally the same as {@link #getAllProviders()}.
1908 *
1909 * @param enabledOnly if true then only enabled providers are included
1910 * @return list of provider names
1911 */
1912 public @Non
Null List<String> getProviders(boolean enabledOnly) {
1913 try {
1914 return mService.getProviders(
null, enabledOnly);
1915 } catch (RemoteException e) {
1916 throw e.rethrowFromSystemServer();
1917 }
1918 }
1919
1920 /**
1921 * Returns a list of the names of available location providers that satisfy the given criteria.
1922 *
1923 * @param criteria the criteria that providers must match
1924 * @param enabledOnly if true then only enabled providers are included
1925 * @return list of provider names
1926 *
1927 * @throws IllegalArgumentException if criteria is
null
1928 *
1929 * @deprecated Criteria based APIs are deprecated, prefer to select a provider explicitly.
1930 */
1931 @Deprecated
1932 public @Non
Null List<String> getProviders(@Non
Null Criteria criteria, boolean enabledOnly) {
1933 Preconditions.checkArgument(criteria !=
null, "invalid
null criteria");
1934
1935 try {
1936 return mService.getProviders(criteria, enabledOnly);
1937 } catch (RemoteException e) {
1938 throw e.rethrowFromSystemServer();
1939 }
1940 }
1941
1942 /**
1943 * Returns the name of the provider that best meets the given criteria. Only providers that are
1944 * permitted to be accessed by the caller will be returned. If several providers meet the
1945 * criteria, the one with the best accuracy is returned. If no provider meets the criteria, the
1946 * criteria are loosened in the following order:
1947 *
1948 * <ul>
1949 * <li> power requirement
1950 * <li> accuracy
1951 * <li> bearing
1952 * <li> speed
1953 * <li> altitude
1954 * </ul>
1955 *
1956 * <p> Note that the requirement on monetary cost is not removed in this process.
1957 *
1958 * @param criteria the criteria that need to be matched
1959 * @param enabledOnly if true then only enabled providers are included
1960 * @return name of the provider that best matches the criteria, or
null if none match
1961 *
1962 * @throws IllegalArgumentException if criteria is
null
1963 *
1964 * @deprecated Criteria based APIs are deprecated, prefer to select a provider explicitly.
1965 */
1966 @Deprecated
1967 public @
Nullable String
getBestProvider(@Non
Null Criteria criteria, boolean enabledOnly) {
1968 Preconditions.checkArgument(criteria !=
null, "invalid
null criteria");
1969
1970 try {
1971 return mService.
getBestProvider(criteria, enabledOnly);
1972 } catch (RemoteException e) {
1973 throw e.rethrowFromSystemServer();
1974 }
1975 }
1976
1977 /**
1978 * Returns the information about the location provider with the given name, or
null if no
1979 * provider exists by that name.
1980 *
1981 * @param provider a provider listed by {@link #getAllProviders()}
1982 * @return location provider information, or
null if provider does not exist
1983 *
1984 * @throws IllegalArgumentException if provider is
null
1985 *
1986 * @deprecated This method has no way to indicate that a provider's properties are unknown, and
1987 * so may return incorrect results on rare occasions. Use {@link #getProviderProperties(String)}
1988 * instead.
1989 */
1990 @Deprecated
1991 public @
Nullable LocationProvider getProvider(@Non
Null String provider) {
1992 Preconditions.checkArgument(provider !=
null, "invalid
null provider");
1993
1994 if (!Compatibility.isChangeEnabled(GET_PROVIDER_SECURITY_EXCEPTIONS)) {
1995 if (NETWORK_PROVIDER.equals(provider) || FUSED_PROVIDER.equals(provider)) {
1996 try {
1997 mContext.enforcePermission(ACCESS_FINE_LOCATION, Process.myPid(),
1998 Process.myUid(),
null);
1999 } catch (SecurityException e) {
2000 mContext.enforcePermission(ACCESS_COARSE_LOCATION, Process.myPid(),
2001 Process.myUid(),
null);
2002 }
2003 } else {
2004 mContext.enforcePermission(ACCESS_FINE_LOCATION, Process.myPid(), Process.myUid(),
2005
null);
2006 }
2007 }
2008
2009 try {
2010 ProviderProperties properties = mService.getProviderProperties(provider);
2011 return new LocationProvider(provider, properties);
2012 } catch (IllegalArgumentException e) {
2013 // provider does not exist
2014 return
null;
2015 } catch (RemoteException e) {
2016 throw e.rethrowFromSystemServer();
2017 }
2018 }
2019
2020 /**
2021 * Returns the properties of the given provider, or
null if the properties are currently
2022 * unknown. Provider properties may change over time, although this is discouraged, and should
2023 * be rare. The most common transition is when provider properties go from being unknown to
2024 * known, which is most common near boot time.
2025 *
2026 * @param provider a provider listed by {@link #getAllProviders()}
2027 * @return location provider properties, or
null if properties are currently unknown
2028 *
2029 * @throws IllegalArgumentException if provider is
null or does not exist
2030 */
2031 public @
Nullable ProviderProperties getProviderProperties(@Non
Null String provider) {
2032 Preconditions.checkArgument(provider !=
null, "invalid
null provider");
2033
2034 try {
2035 return mService.getProviderProperties(provider);
2036 } catch (RemoteException e) {
2037 throw e.rethrowFromSystemServer();
2038 }
2039 }
本文介绍了解决Android应用中LocationManager.getBestProvider方法返回null的问题，主要原因是权限配置错误。通过调整权限配置的位置，确保其放置在</application>标签外，可以有效解决此问题。
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