Updating README for library module

This commit is contained in:
Dimitry Ivanov 2017-05-27 16:27:48 +03:00
parent 2102f325a0
commit ab332e1410
2 changed files with 124 additions and 89 deletions

View File

@ -15,6 +15,9 @@ The aim for this library is to render markdown as first class citizen on Android
The most basic example would be: The most basic example would be:
```java ```java
Markwon.setMarkdown(textView, "**Hello *there*!!**") Markwon.setMarkdown(textView, "**Hello *there*!!**")
// or
Markwon.setMarkdown(textView, spannableConfiguration, "**There <u>hello</u>~~!~~**")
``` ```
Please note, that this library depends on [commonmark-java][commonmark-java] (and some extensions): Please note, that this library depends on [commonmark-java][commonmark-java] (and some extensions):
@ -47,6 +50,92 @@ public Builder htmlParser(SpannableHtmlParser htmlParser);
public SpannableConfiguration build(); public SpannableConfiguration build();
``` ```
## Images
By default this library does not render any of the images. It's done to simplify rendering of text-based markdown. But if images must be supported, then the `AsyncDrawable.Loader` can be specified whilst building a `SpannableConfiguration` instance:
```java
final AsyncDrawable.Loader loader = new AsyncDrawable.Loader() {
@Override
public void load(@NonNull String destination, @NonNull final AsyncDrawable drawable) {
// `download` method is here for demonstration purposes, it's not included in this interface
download(destination, new Callback() {
@Override
public void onDownloaded(Drawable d) {
// additionally we can call `drawable.isAttached()`
// to ensure if AsyncDrawable is in layout
drawable.setResult(d);
}
});
}
@Override
public void cancel(@NonNull String destination) {
// cancel download here
}
};
// `this` here referrs to a Context instance
final SpannableConfiguration configuration = SpannableConfiguration.builder(this)
.asyncDrawableLoader(loader)
.build();
```
There is also standalone artifact that supports image loading *out-of-box* (including support for **SVG** & **GIF**), but provides little to none configuration and could be somewhat not optimal. Please refer to the [README][mil-README] of the module.
## Tables
Tables are supported but with some limitations. First of all: table will always take the full width of the TextView Canvas. Second: each column will have the same width (we do not calculate the weight of column) - so, a column width will be: `totalWidth / columnsNumber`.
## Syntax highlight
This library does not provide ready-to-be-used implementation of syntax highlight, but it can be added via `SyntaxHighlight` interface whilst building `SpannableConfiguration`:
```java
final SyntaxHighlight syntaxHighlight = new SyntaxHighlight() {
@NonNull
@Override
public CharSequence highlight(@Nullable String info, @NonNull String code) {
// create Spanned of highlight here
return null; // must not return `null` here
}
};
final SpannableConfiguration configuration = SpannableConfiguration.builder(this)
.syntaxHighlight(syntaxHighlight)
.build();
```
## Url processing
If you wish to process urls (links & images) that markdown contains, the `UrlProcessor` can be used:
```java
final UrlProcessor urlProcessor = new UrlProcessor() {
@NonNull
@Override
public String process(@NonNull String destination) {
// modify the `destination` or return as-is
return null;
}
};
final SpannableConfiguration configuration = SpannableConfiguration.builder(this)
.urlProcessor(urlProcessor)
.build();
```
The primary goal of additing this abstraction is to give ability to convert relative urls to absolute ones. If it fits your purpose, then `UrlProcessorRelativeToAbsolute` can be used:
```java
final UrlProcessor urlProcessor = new UrlProcessorRelativeToAbsolute("https://this-is-base.org");
```
## Link resolver
Link resolver is used to navigate to clicked link. By default `LinkResolverDef` is used and it just constructs an `Intent` and launches activity that can handle it, or silently fails if activity cannot be resolved. The main interface:
```java
public interface Resolver {
void resolve(View view, @NonNull String link);
}
```
## Theme ## Theme
`SpannableTheme` controlls the appearance of rendered markdown. It has pretty reasonable defaults, which are established based on style of a TextView to which it is applied. It has some factory methods: `SpannableTheme` controlls the appearance of rendered markdown. It has pretty reasonable defaults, which are established based on style of a TextView to which it is applied. It has some factory methods:
```java ```java
@ -153,91 +242,6 @@ public Builder tableBorderWidth(@Dimension int tableBorderWidth);
public Builder tableOddRowBackgroundColor(@ColorInt int tableOddRowBackgroundColor); public Builder tableOddRowBackgroundColor(@ColorInt int tableOddRowBackgroundColor);
``` ```
## Images
By default this library does not render any of the images. It's done to simplify rendering of text-based markdown. But if images must be supported, then the `AsyncDrawable.Loader` can be specified whilst building a `SpannableConfiguration` instance:
```java
final AsyncDrawable.Loader loader = new AsyncDrawable.Loader() {
@Override
public void load(@NonNull String destination, @NonNull final AsyncDrawable drawable) {
// `download` method is here for demonstration purposes, it's not included in this interface
download(destination, new Callback() {
@Override
public void onDownloaded(Drawable d) {
// additionally we can call `drawable.isAttached()`
// to ensure if AsyncDrawable is in layout
drawable.setResult(d);
}
});
}
@Override
public void cancel(@NonNull String destination) {
// cancel download here
}
};
// `this` here referrs to a Context instance
final SpannableConfiguration configuration = SpannableConfiguration.builder(this)
.asyncDrawableLoader(loader)
.build();
```
There is also standalone artifact that supports image loading *out-of-box* (including support for **SVG** & **GIF**), but provides little to none configuration and could be somewhat not optimal. Please refer to the [README][mil-README] of the module.
## Tables
Tables are supported but with some limitations. First of all: table will always take the full width of the TextView Canvas. Second: each column will have the same width (we do not calculate the weight of column) - so, a column width will be: `totalWidth / columnsNumber`.
## Syntax highlight
This library does not provide ready-to-be-used implementation of syntax highlight, but it can be added via `SyntaxHighlight` interface whilst building `SpannableConfiguration`:
```java
final SyntaxHighlight syntaxHighlight = new SyntaxHighlight() {
@NonNull
@Override
public CharSequence highlight(@Nullable String info, @NonNull String code) {
// create Spanned of highlight here
return null; // must not return `null` here
}
};
final SpannableConfiguration configuration = SpannableConfiguration.builder(this)
.syntaxHighlight(syntaxHighlight)
.build();
```
## Url processing
If you wish to process urls (links & images) that markdown contains, the `UrlProcessor` can be used:
```java
final UrlProcessor urlProcessor = new UrlProcessor() {
@NonNull
@Override
public String process(@NonNull String destination) {
// modify the `destination` or return as-is
return null;
}
};
final SpannableConfiguration configuration = SpannableConfiguration.builder(this)
.urlProcessor(urlProcessor)
.build();
```
The primary goal of additing this abstraction is to give ability to convert relative urls to absolute ones. If it fits your purpose, then `UrlProcessorRelativeToAbsolute` can be used:
```java
final UrlProcessor urlProcessor = new UrlProcessorRelativeToAbsolute("https://this-is-base.org");
```
## Link resolver
Link resolver is used to navigate to clicked link. By default `LinkResolverDef` is used and it just constructs an `Intent` and launches activity that can handle it, or silently fails if activity cannot be resolved. The main interface:
```java
public interface Resolver {
void resolve(View view, @NonNull String link);
}
```
## HTML parser ## HTML parser
As markdown supports HTML to be inlined, we need to introduce another entity that does (limited) parsing. Obtain an instance of `SpannableHtmlParser` via one of these factory methods: As markdown supports HTML to be inlined, we need to introduce another entity that does (limited) parsing. Obtain an instance of `SpannableHtmlParser` via one of these factory methods:
@ -247,5 +251,36 @@ SpannableHtmlParser.create(SpannableTheme, AsyncDrawable.Loader)
SpannableHtmlParser.create(SpannableTheme, AsyncDrawable.Loader, UrlProcessor, LinkSpan.Resolver) SpannableHtmlParser.create(SpannableTheme, AsyncDrawable.Loader, UrlProcessor, LinkSpan.Resolver)
``` ```
Or, if further tweaking is requered builder methods:
```java
// creates empty builder
SpannableHtmlParser.builder();
// creates builder that is set-up to default values
SpannableHtmlParser.builderWithDefaults(
@NonNull SpannableTheme theme,
@Nullable AsyncDrawable.Loader asyncDrawableLoader,
@Nullable UrlProcessor urlProcessor,
@Nullable LinkSpan.Resolver resolver
)
```
Builder with defaults additionally handles these HTML tags:
* `b`, `strong`
* `i`, `em`, `cite`, `dfn`
* `sup`
* `sub`
* `u`
* `del`, `s`, `strike`
* `a`
* `img` (only if `AsyncDrawable.Loader` was provided)
You can add own simple tags handling (or override default) via:
```java
SpannableHtmlParser.Builder.simpleTag(String, SpanProvider)
```
Please note, that not all tags are possible to handle via this. These are so called `void` tags ([link](https://www.w3.org/TR/html51/syntax.html#void-elements)) and so-called `html-blocks` ([link](http://spec.commonmark.org/0.18/#html-blocks)). An exception is made only for `img` tag -> it's possible to handle it via `imageProvider` property in `Builder`
[commonmark-java]: https://github.com/atlassian/commonmark-java [commonmark-java]: https://github.com/atlassian/commonmark-java
[mil-README]: https://github.com/noties/Markwon/blob/master/library-image-loader/README.md [mil-README]: https://github.com/noties/Markwon/blob/master/library-image-loader/README.md

View File

@ -63,6 +63,10 @@ public class SpannableMarkdownVisitor extends AbstractVisitor {
private int blockQuoteIndent; private int blockQuoteIndent;
private int listLevel; private int listLevel;
private List<TableRowSpan.Cell> pendingTableRow;
private boolean tableRowIsHeader;
private int tableRows;
public SpannableMarkdownVisitor( public SpannableMarkdownVisitor(
@NonNull SpannableConfiguration configuration, @NonNull SpannableConfiguration configuration,
@NonNull SpannableStringBuilder builder @NonNull SpannableStringBuilder builder
@ -265,10 +269,6 @@ public class SpannableMarkdownVisitor extends AbstractVisitor {
newLine(); newLine();
} }
private List<TableRowSpan.Cell> pendingTableRow;
private boolean tableRowIsHeader;
private int tableRows;
@Override @Override
public void visit(CustomNode customNode) { public void visit(CustomNode customNode) {